First Time Rebuilding Carbs [1984 Honda CM450E] - Questions about float needles

Alright so, a family emergency came up and it kept me busy for a week so I didnt have the chance to work on the bike since I last posted here. Today I finally went to start the bike up for the second time and it was just similar as the first time. started up, idled nice and choke worked fine. I don’t have an RPM gauge so I was just basing this off how much throttle I gave. It would rev fine in the lower rpms but somewhere in the middle, it felt like the power just cut off a bit and then suddenly as I increased throttle, it would come back and be super loud. It is -5* celsius here, and I just wanted to check on the bike to see how it responds to throttle. I’m not sure why it is behaving like this, I do remember reading through LDR post and him saying getting a flat spot is due to the accelerator pump so that is my first suspect. I will also mention that there are a few outside variables that could possibly be affecting this, which include cold weather, engine hasn't been properly turned on in 4 months, valves clearances need to be checked, carbs are NOT synced. I’m not sure if any of these are the culprits. I am planning on for it to get warmer (around 0-7 degrees celsius) and trying again to see if anything changes.
 
I will also mention that the sound the bike made during those mid range rpm sounded like how the bike ran when it would start dumping excess fuel through the overflow tubes.
 
I made my own synchronizing manometer out of 2 clear-glass clean beer bottles, rubber furniture table or chair leg pads that snugly fit the bottles for the bottle caps, drilled just big enough holes thru the rubber caps for the clear flex hose I bought off a spool by the foot at the same Home Depot or Lowe's Home Improvement store I got the rubber furniture leg pads from.

The hose needs to be a snug fit onto the 2 little brass MotionPro threaded synch screws (I got new off eeBay ~$4.00 each) and which screw into the "test port holes" near where the carb intake manifolds bolt to engine cyl-head, and about a half quart of transmission fluid (red) for the liquid to watch rise and fall with vacuum pull from the test ports.

There's a video link somewhere in the carb/fuel sub-forum for our SOHC 450 bikes to a youtube video showing someone do the synch job using a homemade manometer and member "Tomeben" posted a photo of his homemade one. Probly easiest to find it here using forum search function with "homemade manometer" or similar as search term...

..Because you don't know how or if the previous owner(s) or their mechanic(s) ever synched them or if the synch to the engine is still set accurately...
THEN, once synched to engine, the carbs' pilot mixture screws need to be re-set.
Without a tachometer, I guess the mixture screws setting is done only by listening to engine revving higher and then lowering high revving idle speed back down to what sounds like 1100-1300 RPM by turning black plastic knurled-knobbed idle speed screw counter-clockwise to slow the engine down

Maybe consider a nearby motorcycle shop to perform both the synch and pilot mixture re-setting since you don't have a tach ?
Wondering if Sirius Consolidated Inc in Ontario services bikes along with selling bike parts ?
I'd think there's several bike service shops near you and could call around, maybe get a flat-fee qoute over the phone for price shopping the tasks ?
 
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LongDistanceRider said:
Until the carbs are sync'd and then the mixtures set you're wasting your time. Also if the fuel is ethanol added it's likely gone bad or getting there.
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Okay, thanks for letting me know. For once I am happy knowing that I am wasting my time with something lol. I did put stabilizer in the fuel way back in December I think. You think its starting to go bad now? I think I’ll try new fuel regardless just to remove one more possible variable. Okay, when its warmer this week, I’ll try syncing carbs and adjust mixtures (im assuming that is the brass screw on the bottom of the carb near the flow bowls), but will triple check until the day comes.
Boosted said:
I made my own synchronizing manometer out of 2 clear-glass clean beer bottles, rubber furniture table or chair leg pads that snugly fit the bottles for the bottle caps, drilled just big enough holes thru the rubber caps for the clear flex hose I bought off a spool by the foot at the same Home Depot or Lowe's Home Improvement store I got the rubber furniture leg pads from.

The hose needs to be a snug fit onto the 2 little brass MotionPro threaded synch screws (I got new off eeBay ~$4.00 each) and which screw into the "test port holes" near where the carb intake manifolds bolt to engine cyl-head, and about a half quart of transmission fluid (red) for the liquid to watch rise and fall with vacuum pull from the test ports.

There's a video link somewhere in the carb/fuel sub-forum for our SOHC 450 bikes to a youtube video showing someone do the synch job using a homemade manometer and member "Tomeben" posted a photo of his homemade one. Probly easiest to find it here using forum search function with "homemade manometer" or similar as search term...

..Because you don't know how or if the previous owner(s) or their mechanic(s) ever synched them or if the synch to the engine is still set accurately...
THEN, once synched to engine, the carbs' pilot mixture screws need to be re-set.
Without a tachometer, I guess the mixture screw setting is done only by listening to engine revving higher and then lowering high revving idle speed back down to what sounds like 1100-1300 RPM by turning black plastic knurled-knobbed idle speed screw counter-clockwise to slow the engine down

Maybe consider a nearby motorcycle shop to perform both the synch and pilot mixture re-setting since you don't have a tach ?
Wondering if Sirius Consolidated Inc in Ontario services bikes along with selling bike parts ?
I'd think there's several bike service shops near you and could call around, maybe get a flat-fee qoute over the phone for price shopping the tasks ?
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it’s tough for me to move the bike around since I dont have a pick up truck so it just leaves room for me to rent one which can be any where from $50-$60 when gas is accounted for. My original plan was to only have to rent a truck when I will get my motorcycle safetied but if it still gives me issues after carbs are synced, then I think I will consider it. I do have a carb sync gauge that a coworker from work allowed me to borrow, its those $30 amazon ones, people have mix reviews on those one but I think I’ll give it a shot with that.

I think I saw this homemade manometer thing and I thought it was really cool and considered doing it just because of seeing how it worked, so if this loaner syncer doesn’t work, then I guess im taking a trip down to home depot.

I am pretty sure these carbs haven’t been synced in 20 years at least, it was last insured in 2000, and I know it sat for awhile before I got ahold of it. I’ll make this my top priority.
 
I also noticed a slight ticking sound which I wasn’t too sure what it was, it never had this sound before, so I assumed it was just some loose bolt vibrating somewhere on the bike (wheel is still currently off so a few loose screws here and there) or my fuel tank vibrating because it wasn’t properly secured. However, I also think it may also be valve clearance issue which is what I had originally planned on doing after carbs, but now I am thinking if that could also be what’s messing with my carbs.
 
The vacuum test ports for the synch check are plugged with a small 5mm JIS-Phillips #2 screw and flat "sealing" washer -
-reminder to make sure your #2 driver (JIS or Pozi-Drive, etc..) fits the cross snugly and,
since it's been decades since they were last touched,
a drop or two of Liquid Wrench (or, other penetrant) onto them along with a couple of straight-at-it wrap-taps to break the corrosion
before attempting to unscrew them.

"Ticking" - adjective best used to describe valve-train clatter...
..the next task on one of my bikes (19k mi) is to return to its valve-train for the 3rd time
to see the condition of the valve-stem tops and tappets hoping to find the source of a slightly abnormal ticking sound I'm hunting.
The first 2 times was to check, adjust and double-check the clearances.
This next 3rd time, I'll be removing the tappets for microscope examination looking for severe damage (mushrooming or deep punch marks) from someone before me setting with too-small clearances causing "hammer-time"
 
Boosted said:
The vacuum test ports for the synch check are plugged with a small 5mm JIS-Phillips #2 screw and flat "sealing" washer -
-reminder to make sure your #2 driver (JIS or Pozi-Drive, etc..) fits the cross snugly and,
since it's been decades since they were last touched,
a drop or two of Liquid Wrench (or, other penetrant) onto them along with a couple of straight-at-it wrap-taps to break the corrosion
before attempting to unscrew them.

"Ticking" - adjective best used to describe valve-train clatter...
..the next task on one of my bikes (19k mi) is to return to its valve-train for the 3rd time
to see the condition of the valve-stem tops and tappets hoping to find the source of a slightly abnormal ticking sound I'm hunting.
The first 2 times was to check, adjust and double-check the clearances.
This next 3rd time, I'll be removing the tappets for microscope examination looking for severe damage (mushrooming or deep punch marks) from someone before me setting with too-small clearances causing "hammer-time"
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its been ages since they were last touched and from previous experiences from the carbs, I am going to make sure whatever tool I use, will be a snug fit for those vacuum screws. I ordered a valve cover gasket #12328-413-830 from Partzilla and a couple of NGK DR8ES-L spark plugs (what the manual said to use however I was thinking of going with iridium spark plugs), so going to do a clearance checks soon and change plugs. I might still try carb syncing one more time this Wednesday when its warmer, just to see if that will solve the problem just because it’ll take some time before my parts come in - however, if I’m still wasting my time, let me know. I had originally planned on doing valve clearances, spark plugs, and adjusting the balancer chain tension, but carbs came in the way unfortunately so I spent all my time on that.

You’re saying after adjusting and double checking clearances for the valves that it still made the ticking noises?? That would’ve driven me nuts! From watching a video on how to do these valve clearances, the guy said that its better to have them too lose than too tight so I think I’ll keep that in mind when i check mine.
 
Valve cover gaskets are good until they're torn, or cut, or pinched to death from over-tightening the 2 bolts that install the valve cover on top. So keep that new as a spare until yours allows a leak...
Iridium tipped plugs - unnecessary until NGK and Denso, etc. discontinue making the standard plugs (copper-core?) but if they last 100,000+ miles in car/truck engines (as "claimed"), then maybe their higher price is reason enough...

Reminder: Valve tappet "clearance" checks/adjustments and balancer chain tension done ONLY with overnite-cold engine
And, yes, slightly-loose clearances are better than too-tight, for the "Hammer Time" reason mentioned earlier...
 
I
Boosted said:
Valve cover gaskets are good until they're torn, or cut, or pinched to death from over-tightening the 2 bolts that install the valve cover on top. So keep that new as a spare until yours allows a leak...
Iridium tipped plugs - unnecessary until NGK and Denso, etc. discontinue making the standard plugs (copper-core?) but if they last 100,000+ miles in car/truck engines (as "claimed"), then maybe their higher price is reason enough...

Reminder: Valve tappet "clearance" checks/adjustments and balancer chain tension done ONLY with overnite-cold engine
And, yes, slightly-loose clearances are better than too-tight, for the "Hammer Time" reason mentioned earlier...
Click to expand...
I want to clarify, ONLY do valve tappet, and balancer chain when I HAVEN’T turned the engine on, and it is kept cld? Just out of curiosity, how come?
 
Valve clearances are set with a cold engine because the temperature will remain constant during the process. A hot engine will be loosing temp as soon as it's shut down and that means things are contracting as they cool. Not to mention working on a hot engine results in injuries usually like ugly burns.
As for the balancer oil vapor will be blown in your face while doing it running.
 
Yeah, metals grow and expand and soften with heat and is one more reason to wait minimum of 10 minutes before unscrewing a steel spark plug out of a hot engine's aluminum cylinder head - you risk damaging the softer aluminum threads of the hole for the spark plug. Like a wrought iron-smith's occupation - they get their metals RED HOT so to be able bend and form them into the desired shape. Same reasoning in a valve tappet check - Imagine trying to unlock the tappet locking nuts while at operating temp hot : the threads of both the nut and tappet are expanded and softer and the nut is also expanded in size and locking against the rocker arm. Unscrewing it would shear metal off of the nut and stretch and smoosh and damage the softer hot threads.
 
I haven't been around for a while to respond to this thread. With regards to the boots you can use regular wheel bearing grease or "red rubber grease" to help slide the insulator and air box boots on. What I do is get the carbs on the insulators and get them finger tight on the clamps. Then shift the air box up and on to the carbs. Then tighten the boots. I remove the bolts on the side for the air box as well. You don't have to remove the rear fender for the air box. Rather, you can loosen the two bolts on the side and the remove the two at the top where the seat bracket is and then shift it UP and you'll have room to work and move the box around.

With the mid range being bunk wait until the bike is fully warm, about 10 miles. The bike may run with the choke down during the first 10 minutes but I've found most of them tend to have a dead/lean spot at mid throttle until it's fully warmed up. You want to gradually move the choke down as you drive the first 10 minutes. If it's still too lean at mid throttle you probably have the floats too low. I had this problem on mine after a total rebuild and the floats were closer to 18mm. Set them to 14.5mm and runs perfect. I like to check the floats with them on the bike and the bowls off, but you can just get them up right and set it. Most people get tripped up on the plunger on the float valve. When it kisses the plunger that's the float height. But you can do it visually by turn on the petcock to a trickle (lay down towels, do it outside) and push up on the float very slowly until it starts trickling along the stantations then up a bit more where that stops and that's the height.

For valves I just set the intake at 0.006" and the exhaust at 0.008". If you dislike this then do 0.004" for intake and 0.006" for exhaust. Don't go any lower than that.

With the bike running and fully warm set the cam chain tension by loosening the 10mm nut at the bottom of the cylinder head. I believe you did a total rebuild, yes? If you replaced the cam chain and the slipper then don't expect it to do anything. Otherwise you may need to do it and if it hasn't been done in who-knows-how-long you may have to go a full turn or two until you hear banging around in the head and then tighten it up. When it bangs around typically you can also feel the noise travel to the wrench.

If the bike is idling OK then sync is probably close enough. Iridium's are a waste of money and may not fire correctly. Just get some NGK D8EA plugs.

When doing the pilot mixture, with the bike fully warm after 10 minutes of RIDING (don't just let it sit there for 10 minutes on the stand it might not be enough), pick a side, put a box fan up to the engine so you don't overheat it, turn the pilot mixture screw in or out a bit then blip the throttle. If the idle "hangs" for a brief moment then returns back to where it should be (i.e. ~1100-1200RPM) then it's too lean so turn the screw OUT. Conversely if the idle "drops" below the target idle and then returns to it it's too rich. You can do it with a sync gauge by watching the rise and fall. But you can do it by ear by just turning the screw in just until stumbles (it should all the way in, if it does not then very likely the tip on the mixture screw is bent, get a new one aftermarket is OK) then go out until the idle sounds really nice then go out a bit more until it gets rough again. Blip the throttle, then go back in again until it sounds good, blip the throttle again. Repeat for the other side. Go for a ride. Put a load on the bike and either pull the clutch in or engine brake. If it back fires and you're certain it is not exhaust joints then listen for the offending side and turn the screw out a 1/8" to 1/4" turn and try it again.

Make certain to check that both pilot mixture screws will bog out the engine and cause it to die or just about when turning them in until fully seated. If they don't inspect the tips on the screws. If those are good make sure the washer, spring and o-rings are there on the screw and use a new o-ring if it's a flat piece of plastic. If still no good then you have something obstructed in the idle circuit.

EDIT: Additional stuff here. If the compression is good (150PSI or higher) and fairly equal on both sides then you SHOULD be able to do a bench sync (carbs off the bike) and turning the sync adjuster and idle speed adjuster screws in and out until they're about half way on the first bypass port that the throttle plates cover. Get them equal on both sides, snug it up and check again. I didn't go back to see if you did a bench sync, if you didn't then just wait for the sync gauges or build one. I've done the bypass port bench sync method a few times on some customer bikes where the engines were in good health and verified with sync gauge. They tend to be 2-4cmHG off with this method. Within spec. You can get it tighter to be practically equal, however the only real difference there is that it might be a slightly smoother idle.

I know you mentioned the D8EA resistor plug versions, you can use that or the regular D8EAs. The Canadian models have a total of 10K resistance with a 5K cap and the 5K resistor plug. 5K total resistance (i.e. just a resistor cap) will be fine. I believe the non-resistor plugs are cheaper as well.
 
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Maraakate said:
"hangs" for a brief moment then returns back to where it should be (i.e. ~1100-1200RPM) then it's too lean so turn the screw OUT. Conversely if the idle "drops" below the target idle and then returns to it it's too lean
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Both situations you said 'too lean'. Did you mis-speak?
 
IMMENSELY helpful explanation. I’ll address a few points here.

Before I get into it. I just want to restate that the current issue that I am dealing with is that mid range RPM, the bike bogs. I haven’t got the chance to ride it yet as I am waiting for the snow to clear up, but currently, when its in neutral and bogs, it sounds very similar to how the bike would suddenly start bogging before I had rebuilt the carb. (This bogging came out of nowhere, and was running perfectly fine before). Here are a few things I have noticed on my bike after inspecting. First off, I notice the mixture screws on the bottom are not in the same orientation (the flat head part of the screw are not align with each other and one is slight off), I don’t know if this could cause this issue. Another thing is it looks like I have a hole at the end of my muffler right next to the exhaust exit. Noticed it when I started the bike up in the winter and saw exhaust smoke coming from there (quite a hole, but didnt think it would affect the bike other than making it louder.
Maraakate said:
With the mid range being bunk wait until the bike is fully warm, about 10 miles. The bike may run with the choke down during the first 10 minutes but I've found most of them tend to have a dead/lean spot at mid throttle until it's fully warmed up. You want to gradually move the choke down as you drive the first 10 minutes. If it's still too lean at mid throttle you probably have the floats too low. I had this problem on mine after a total rebuild and the floats were closer to 18mm. Set them to 14.5mm and runs perfect. I like to check the floats with them on the bike and the bowls off, but you can just get them up right and set it.
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So I think I let the bike warm up for 5 minutes before blipping the throttle so I think, that’s my first mistake. I have not properly warmed it up for a solid 10 minutes and haven’t drove it either. Another thing I want to mention is that the carb for this bike had non adjustable float height, and when I measured it after assembling together, it has measured 15.5mm - which was what LDR had mentioned in his VB carb rebuild thread.
Maraakate said:
For valves I just set the intake at 0.006" and the exhaust at 0.008". If you dislike this then do 0.004" for intake and 0.006" for exhaust. Don't go any lower than that.
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Valve clearances, I was following the service manual, 10mm and 14mm, but knowing that I shouldn’t go any lower than that, I may just go a little higher just to be on the safe side.

I did not do an engine rebuild, I hope I didn’t mention that anywhere and confused yall, just getting into my motorcycle journey right now. I doubt the chain has been adjusted in 20 years, its the next thing on my list after carbs and valves.
Maraakate said:
If the bike is idling OK then sync is probably close enough.
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The bike idles, starts up pretty easily and idles smoothly. I did bench sync it following LDRs guide before I threw the carbs onto the bike. Its revving the engine thats giving me problems.
Maraakate said:
When doing the pilot mixture, with the bike fully warm after 10 minutes of RIDING (don't just let it sit there for 10 minutes on the stand it might not be enough), pick a side, put a box fan up to the engine so you don't overheat it, turn the pilot mixture screw in or out a bit then blip the throttle. If the idle "hangs" for a brief moment then returns back to where it should be (i.e. ~1100-1200RPM) then it's too lean so turn the screw OUT. Conversely if the idle "drops" below the target idle and then returns to it it's too rich. You can do it with a sync gauge by watching the rise and fall. But you can do it by ear by just turning the screw in just until stumbles (it should all the way in, if it does not then very likely the tip on the mixture screw is bent, get a new one aftermarket is OK) then go out until the idle sounds really nice then go out a bit more until it gets rough again. Blip the throttle, then go back in again until it sounds good, blip the throttle again. Repeat for the other side. Go for a ride. Put a load on the bike and either pull the clutch in or engine brake. If it back fires and you're certain it is not exhaust joints then listen for the offending side and turn the screw out a 1/8" to 1/4" turn and try it again.

Make certain to check that both pilot mixture screws will bog out the engine and cause it to die or just about when turning them in until fully seated. If they don't inspect the tips on the screws. If those are good make sure the washer, spring and o-rings are there on the screw and use a new o-ring if it's a flat piece of plastic. If still no good then you have something obstructed in the idle circuit.
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I haven’t got the chance to carb sync yet due to cold weather, but I will try following your guide on the mixture screws and come back to you. If I can recall correctly, carb sync then adjust mixture screws?
 
Also, for carb syncing, how do you guys reach the balancing/sync screw for the right carb? I saw that you had to use this specialized unique tool but anyway to do it using wrenches and a flat head? It looks so tight to even put the OEM tool in. EB61DC41-746A-46FE-AE0B-A84534972C56.jpegD6F01821-F476-4A2A-8617-9F6639B52ED2.jpeg
No access ports on the top of the bike

LDR reccomended using a long flat head and a wrench but it was too tight to fit the wrench in for me.
 
Correct, sync the carbs followed by mixture adjustment.
I use Honda specs for the carbs and valves.
Yeah, access sucks and that's why people hate doing the sync. Reach in above the boots with an 8mm wrench to loosen the nut. Then use a long(12") thin screwdriver for the screw. You'll be at a stupid angle but it'll work.
 
LongDistanceRider said:
Correct, sync the carbs followed by mixture adjustment.
I use Honda specs for the carbs and valves.
Yeah, access sucks and that's why people hate doing the sync. Reach in above the boots with an 8mm wrench to loosen the nut. Then use a long(12") thin screwdriver for the screw. You'll be at a stupid angle but it'll work.
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These carbs are designed to infuriate me more and more :cautious:

Thanks tho!
 
dougrun said:
that tool is well worth it.
www.z1enterprises.com

Adjustment Tool Set - Carburetor - 11 inch

Color/Finish: Black/Natural Material: Steel/Plastic Dimensions: 11in length Fits: Mikuni / Keihin 8mm hex nut
www.z1enterprises.com www.z1enterprises.com
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What angle would you approach the bike with this in my scenario? I’m assuming these are designed for frames that have cavities under the fuel tank tank for u to be able to reach the screw? Correct me if I am wrong though, I am not too familiar with this doohickey.
 
What is the compression and have you done a leak down test? If it's low then the carbs will require enrichment to compensate.

A half-hearted hack you can do to verify if it's too lean is to just stuff the air filter with a few shop rags and see if it magically runs better. You can also ride with half choke up. I will say that 5 minutes is not sufficient to remove the dead mid-range with choke all the way down. It's about 10 minutes. Depends on how much you're driving in that time. Sometimes it's sooner if you're cruising.

If it's idling OK very likely sync is close to where it needs to be and you should be able to set mixture screws now. Honestly, if it's idling OK and after full warmup you blip the throttles and it returns to idle just fine then you can leave it be for right now. The screws not being exactly in the same spot is fine.

These are non-adjustable floats, however you can change them to the earlier years with the adjustable floats on this model. However, hold off on that until you get things dialed in.

Adjust the cam chain as soon as you can. This matters and can affect performance. We went through this problem with @esh21167 400T where it was overheating and causing funny running after 10 minutes.

It's also possible that the needle jet/jet needle combo is incorrect for your model (aftermarket replacement) and causing the dead spot. If you get a chance sometime you can remove one of the covers while still on the bike and pull the CV piston out and look at the numbers on the needle and let us know.
 
Also, despite internet lore some holes in the exhaust won't affect performance like you think it does. It may cause some popping on decel, but it's so minor to actually affect overall performance. I know because I've ridden around with holes in the exhaust on these bikes and a customer bike I'm working on has Harley Sporster mufflers and my own bike has an aftermarket exhaust collector. No discernible change in performance in any of these, so I wouldn't worry about that.
 
TomatoThePotato said:
What angle would you approach the bike with this in my scenario? I’m assuming these are designed for frames that have cavities under the fuel tank tank for u to be able to reach the screw? Correct me if I am wrong though, I am not too familiar with this doohickey.
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From the left side of the bike you'll get an angle, right against the frame and IIRC slightly forward of the nut.
 
Maraakate said:
What is the compression and have you done a leak down test? If it's low then the carbs will require enrichment to compensate.

A half-hearted hack you can do to verify if it's too lean is to just stuff the air filter with a few shop rags and see if it magically runs better. You can also ride with half choke up. I will say that 5 minutes is not sufficient to remove the dead mid-range with choke all the way down. It's about 10 minutes. Depends on how much you're driving in that time. Sometimes it's sooner if you're cruising.

If it's idling OK very likely sync is close to where it needs to be and you should be able to set mixture screws now. Honestly, if it's idling OK and after full warmup you blip the throttles and it returns to idle just fine then you can leave it be for right now. The screws not being exactly in the same spot is fine.

These are non-adjustable floats, however you can change them to the earlier years with the adjustable floats on this model. However, hold off on that until you get things dialed in.

Adjust the cam chain as soon as you can. This matters and can affect performance. We went through this problem with @esh21167 400T where it was overheating and causing funny running after 10 minutes.

It's also possible that the needle jet/jet needle combo is incorrect for your model (aftermarket replacement) and causing the dead spot. If you get a chance sometime you can remove one of the covers while still on the bike and pull the CV piston out and look at the numbers on the needle and let us know.
Click to expand...

Haven’t done compression test or leakdown test yet, was contemplating if I should I do a leak down test but I do not have an air tank available so was thinking about doing only a compression test, but haven’t full decided yet.

I don’t think these carbs have been tampered with before me (I thought they were but I was mistaken) but I did not change anything on the carbs aside from the gaskets and screws to hold it together and drainage screws. So from what I know, it should all be OEM, I’ll see if I have a picture of the needle to see if theres a number though.

Do you think 15.5 mm is fine for floats? I am a little confused because there’s two numbers floating around now.

just to verify with you, the carb sync is fine for now and I should adjust the mixture screws following your guide the next time I work on the bike AFTER I have done valve clearance. But before adjust mixture screws, warm the bike up by riding for 10 minutes.


P.S
my current list of to do is as follows:
Valve clearance
Carb
Spark plugs
Cam chain and Balance chain
Compression Test (maybe leakdown test if I can get a hold of a tank)
(might be forgetting things but let me know).

Optional: Get oil analyzed to see health of engine. (Blackstone labs?)
 
15.5mm is stock, I've found 14.5-15.0mm (a little more richer) seems to work the best. It's not required.

I wouldn't adjust anything carb related until you get the NGK XD05F caps and plugs. You CAN do this in the mean time:

* Do compression test. Don't use a crappy compression tester like $20 special on Amazon. Get an OTC, borrow a snap-on one, or limp it to a motorcycle shop and have them do it. Crappy testers will give you wild results. When doing the compression test choke is OFF and throttle is WIDE OPEN. It DOES matter on bikes.
* Adjust valves.
* With bike running do cam tension.

EDIT: Getting oil analyzed is a waste of time since you're still tuning the bike up. DO however, get some MOTORCYCLE SPECIFIC 10W40. Honda GN4 is probably the cheapest. Synthetics will be a waste of money. If you're only riding when it's mostly warm out then Rotella T4 15W40 will also work. It's not motorcycle specific but meets the JASO requirements.
 
A final thought before I sign off for right now. Depending on how lean the mid range spot is it CAN be the primary jet has fallen loose and is floating around in the bowl. I've had this happen before. If the needle jet holder falls out it can cause you to lose mid to top end range.
 
Maraakate said:
A final thought before I sign off for right now. Depending on how lean the mid range spot is it CAN be the primary jet has fallen loose and is floating around in the bowl. I've had this happen before. If the needle jet holder falls out it can cause you to lose mid to top end range.
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Appreciate the help, the compression test is painful knowing that the amazon ones are crap. I’ve gotten the spark plugs already, however I’ll look into getting those caps as well.

I’ll check the float bowles for any loose primary jets. I’m hoping this is the issue so I can put this all behind me. :cry:
 
You can drop the bowls on the bike carefully by taking a 1/4" ratchet with a 1/4" socket and putting a #2 bit in the 1/4" socket.
 
 
TomatoThePotato said:
Also, for carb synchring, how do you guys reach the balancing/sync screw for the carb?
I saw that you had to use a uniquely specialized tool, but is there anyway to do it using wrenches and a flat head? It looks too tight to even put the OEM tool in - No access ports on the top of the bike frame.
LDR recommended using a 12" long flat head and a wrench but it was too tight to fit the wrench in for me.
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Following LongDistanceRider's way, I used my 11"-long skinny-shaft flat-head screwdriver to turn the synchro screw and
once they were synched (red ATFluid levels in my homemade manometer bottles no longer rising or falling)
I sighted the direction of the slot REAL GOOD, switched off engine and key, then twisted throttle grip so to position locknut from horizontal to vertical so to be able to much more easily lock synch screw with 8mm wrench.
And then released throttle grip so to verify that the slot didn't rotate clockwise from where I'd sighted it while locking its locknut.

Took me 3-4 attempts, but as the elders have shown, taught : Repetition makes The Master !

And I've never heard of OTC (OverTheCounter ? ..lol), but I'd bought this for compression testing with an instant 20-25% off website discount code at Advance Auto Parts dot com bringing the total to +/-$55 U.S. :

www.innova.com

3614 Compression Tester Plus (6-piece kit)

The Innova 3614 is designed with a stainless-steel hose for ultimate reliability and longevity. Featuring several different sized adapters, including long reach, the 3614 provides functionality all different kinds of engine applications.
www.innova.com www.innova.com
 
Try Partsource or Canadian Tire, as they have a tool loaner program that may include a comp tester in their tool selection. If you wish to purchase one I use the Innova one shown above and it is a good unit. It has come down in price from years past and is cheaper now at around $50 Canadian if your interested on Amazon Canada.
 
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