1972 CB450 K5 Hot Mess

Thanks for looking and I saw these as well on ebay earlier today and I am wondering when they will start making knock offs of these if supply is getting short. Thank you for checking to see if you have an extra but you may want to hold on to it.
 
Went ahead and ordered the pizza cutter. At least there was a discount code that almost paid the shipping.
 
RobMan said:
Here are pics of the forks from the CB450. The left fork is pretty much a fishing weight unless there is a way to repair these.
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Yes, anytime a shift fork has a half-circle burned/scored area it's done. Honestly, the ones with the nicked/worn tips aren't the greatest either.

CB450, last picture, far right one looks good, far left not
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CL450

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The shift forks are the connection between the shift drum and the transmission gear. This is called a function group because all these parts have one overall function. When you see wear on the shift forks, you should look at all components in this function group, not only the shift forks.

The whole group is larger, being:

- pizza cutter
- shift drum
- shift drum groove
- shift fork pin
- shift fork guide
- shift fork "hammer head area" (as you call it)
- transmission gear groove (where the shift fork slides in)
- transmission gear
- transmission shaft

All these parts have a certain tolerance, and the total, cumulative, tolerance will have influence on the amount of wear and pattern.

For example, if the radial play of the shift fork to the shift drum is too large, the shift fork can tilt under force, touching the gear tooth, with the result in a typical wear pattern pointed out by AD. In your case, the "hammer heads " are (probably) good to go (measurements will reveal this), it's the tilting that is the issue here. But it's more complex than this, tilting of the forks is one possibility, tilting of the gear the other one. A tilting gear could mean a worn gear or a worn gear shaft. In most cases, tilting is caused by radial play between gear and shaft.

Looking at the wear patterns of all the parts in the function group will reveal the real reason behind the wear on the sift forks, and in most cases this is not a single part. Replacing the parts with the largest tolerances (low-hanging fruit) will improve shifting accuracy and result in less wear.

The above is just an example, I also have seen shift drum bearings completely worn out, resulting in a tilting shift drum, causing wear on all shift forks while the shift fork to drum play, and shift fork to gear play was minimal.

Unfortunately, the real issue is mostly the gear to shaft radial play, the gear will tilt and hit the shift drum, causing typical wear as AD pointed out. Replacing the shift fork will take away the play between drum and fork, thus tilting between those parts, but not the tilting between gear and shaft.

In your case, the wear pattern on the "hammer heads" is only at the tips, meaning tilting of the gear is probably your enemy.
 
jensen said:
The shift forks are the connection between the shift drum and the transmission gear. This is called a function group because all these parts have one overall function. When you see wear on the shift forks, you should look at all components in this function group, not only the shift forks.

The whole group is larger, being:

- pizza cutter
- shift drum
- shift drum groove
- shift fork pin
- shift fork guide
- shift fork "hammer head area" (as you call it)
- transmission gear groove (where the shift fork slides in)
- transmission gear
- transmission shaft

All these parts have a certain tolerance, and the total, cumulative, tolerance will have influence on the amount of wear and pattern.

For example, if the radial play of the shift fork to the shift drum is too large, the shift fork can tilt under force, touching the gear tooth, with the result in a typical wear pattern pointed out by AD. In your case, the "hammer heads " are (probably) good to go (measurements will reveal this), it's the tilting that is the issue here. But it's more complex than this, tilting of the forks is one possibility, tilting of the gear the other one. A tilting gear could mean a worn gear or a worn gear shaft. In most cases, tilting is caused by radial play between gear and shaft.

Looking at the wear patterns of all the parts in the function group will reveal the real reason behind the wear on the sift forks, and in most cases this is not a single part. Replacing the parts with the largest tolerances (low-hanging fruit) will improve shifting accuracy and result in less wear.

The above is just an example, I also have seen shift drum bearings completely worn out, resulting in a tilting shift drum, causing wear on all shift forks while the shift fork to drum play, and shift fork to gear play was minimal.

Unfortunately, the real issue is mostly the gear to shaft radial play, the gear will tilt and hit the shift drum, causing typical wear as AD pointed out. Replacing the shift fork will take away the play between drum and fork, thus tilting between those parts, but not the tilting between gear and shaft.

In your case, the wear pattern on the "hammer heads" is only at the tips, meaning tilting of the gear is probably your enemy.
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Jensen, could end play in the shaft or its gears also cause these shift fork areas to come into contact, that were not designed to ever come in contact?
 
jensen said:
In your case, the wear pattern on the "hammer heads" is only at the tips, meaning tilting of the gear is probably your enemy.
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Thank you and I will take a hard look at all the areas where that wear can occur. As part of this rebuild I have invested in micrometers and a dial indicator so I can do a better job of measuring wear like you are describing using the FSM where I previously got by with a set of calipers and a straight edge and the Mark II eyeball. I know I am a bit fixated on the forks at the moment but that is in direct relation to when I notice an issue with a part and then after I check availability and prices. I have just finished tearing down both engines completely and I am going to start cleaning and a part by part comparison using the best parts for the build. Of course if something is worn beyond tolerances or obviously damaged it will have to be replaced but cost has to be factored in. One thing I have noticed since starting this project is the relationship between parts that tend to wear out quicker and the availability of those parts and prices from vendors. Anyway thanks again for emphasizing a careful check of the components because I really don't want have a failure after investing a great deal of time and money.
 
Jensen, could end play in the shaft or its gears also cause these shift fork areas to come into contact, that were not designed to ever come in contact?
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Hi BB, maybe, but never seen, at least not as main reason.
 
Thank you and I will take a hard look at all the areas where that wear can occur. As part of this rebuild I have invested in micrometers and a dial indicator so I can do a better job of measuring wear like you are describing using the FSM where I previously got by with a set of calipers and a straight edge and the Mark II eyeball. I know I am a bit fixated on the forks at the moment but that is in direct relation to when I notice an issue with a part and then after I check availability and prices. I have just finished tearing down both engines completely and I am going to start cleaning and a part by part comparison using the best parts for the build. Of course if something is worn beyond tolerances or obviously damaged it will have to be replaced but cost has to be factored in. One thing I have noticed since starting this project is the relationship between parts that tend to wear out quicker and the availability of those parts and prices from vendors. Anyway thanks again for emphasizing a careful check of the components because I really don't want have a failure after investing a great deal of time and money.
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If you have two engines, and two complete transmissions, use the best parts from both, starting with the main and counter shaft. Take a (critical) look at the splines, especially the diameter over the splines in the area where the M2/3 (main shaft 2nd / 3th), C4 (counter shaft 4th) and C5 (counter shaft 5th) ride. Also measure the tilt of those gears in this area, of both sets of shafts, and both sets of gears and combine them until you find the smallest tilt combination.
 
Cleaned the upper case that I will be using from the CL450 donor engine and then fished for metal with the magnet to see how it compared with the lower case. There was quite a bit of attached but it was more of a paste rather than shiny bits as @jensen had remarked about in post 241. Image is a bit out of focus.

IMG_4416.JPG


After I finished that I decided to chase out the threads in the bolt holes in both cases. I don't have an actual thread chaser and I really don't like using a tap unless I have to so I cleaned each hole with brake cleaner and then used a drop of tap magic and ran a bolt down each hole and if there was any resistance, wash out with brake clean and try again. Thankfully I had no issues with any of them except the one 6MM bolt that was previously broken off in the lower case which I am gong to take to the machinist to remove. If I remember correctly there was a discussion about speed handles a while back I thought I would include a pic of mine. For me it was the perfect tool for this task as I didn't want to run the bolt in with a power tool and a ratchet would have been tedious.

IMG_4417.JPG
 
Been doing Honey Do's and chores so haven't worked on any thing lately other then taking a few minutes to check the wear on the old neutral stoppers using my calipers and saw that one had about 0.005 and the other had about 0.008 inch side to side play. Coincidentally got an offer for a few dollars off on a NOS one on ebay that @ancientdad which about pays the shipping so went ahead and ordered it. I had already ordered the pizza cutter and received it yesterday so both will be new. Hopefully after re-staining the deck this weekend I will get some time off for good behavior and can get the parts that need fasteners removed to the machinist next week and start doing a close inspection of the kick stater and transmission parts.
 
Wanted to share a quick update. I have been finished cleaning engine cases and covers and slowly and carefully scraping baked on gaskets. I saw where @jensen had mentioned using oil to soften the gaskets and I had found that Sea Foam seems to work better for me, certainly better than Permatex gasket remover. I started using it on my S90 when I had the out for the top end and and chad all the covers off. I have at least four fasteners for the machinist to work on for me this week. Also took a look at the transmission shafts from both the CB and CL and overall the CL looks fine but did notice a flaw on the CB counter shaft on one of the areas where the shift fork rides. I want to use the CB shat as it does not have the chain oiler so may mix and match a bit.

IMG_4426.JPGIMG_4425.JPG
 
I saw where @jensen had mentioned using oil to soften the gaskets and I had found that Sea Foam seems to work better for me, certainly better than Permatex gasket remover.
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We don't have sea-foam in the Netherlands, as far as I know, (used) oil is a good substitute.
 
RobMan said:
Also took a look at the transmission shafts from both the CB and CL and overall the CL looks fine but did notice a flaw on the CB counter shaft on one of the areas where the shift fork rides. I want to use the CB shat as it does not have the chain oiler so may mix and match a bit.
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Is that actually a crack? It certainly looks like one in the picture. Can't say I've ever seen that before either, but the older these bikes get and the more abuse they've taken over the years, the more unusual stuff we'll see I'm sure.
 
jensen said:
We don't have sea-foam in the Netherlands, as far as I know, (used) oil is a good substitute.
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If your not familiar with it, it is an additive that is supposed to be for fuel or oil but I have only used to add to fuel occasionally. Light oil, naphtha and Isopropyl Alcohol are the basic ingredients I believe.
 
ancientdad said:
Is that actually a crack? It certainly looks like one in the picture. Can't say I've ever seen that before either, but the older these bikes get and the more abuse they've taken over the years, the more unusual stuff we'll see I'm sure.
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I don't think it is a crack but I will have to disassemble to get a really good look. To me it appears that a thin layer of the metal has peeled away from the machined surface. If you go back to post 428 you can see the images of the forks and the left fork is badly worn which I think would match up to this area. I am going to dissemble each shaft for cleaning and take another look and assemble the best of both, kinda like a greatest hits album.
 
RobMan said:
I don't think it is a crack but I will have to disassemble to get a really good look. To me it appears that a thin layer of the metal has peeled away from the machined surface. If you go back to post 428 you can see the images of the forks and the left fork is badly worn which I think would match up to this area. I am going to dissemble each shaft for cleaning and take another look and assemble the best of both, kinda like a greatest hits album.
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Pictures can be deceiving, hopefully your mix and match will result in a serviceable set. If I decide to build one of my 5 speed bottom ends I'll be in the same position with a pair of engines to combine from.
 
Just a thought. It's so helpful when you take a photo of something that seems strange, because you can blow up the picture easily on a screen. My old eyes don't focus well on tiny things, especially in low contrast spots. I was able to see the wear on that gear very clearly!
 
wentwest said:
Just a thought. It's so helpful when you take a photo of something that seems strange, because you can blow up the picture easily on a screen. My old eyes don't focus well on tiny things, especially in low contrast spots. I was able to see the wear on that gear very clearly!
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Same here, I used to have super vision but no longer. I thought it was a small strand of lint or dirt at first and was using a magnifying lamp but could feel the imperfection with a scribe. I was kinda shocked to see how bad it was in the photo myself. I need a new phone with a better camera for low light images.
 
Same here, I used to have super vision but no longer. I thought it was a small strand of lint or dirt at first and was using a magnifying lamp but could feel the imperfection with a scribe. I was kinda shocked to see how bad it was in the photo myself. I need a new phone with a better camera for low light images.
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Or adding good light, cheaper as well ;)
 
Took the lower case and right cover which is a spare to the machinist Tuesday to repair a broken 6MM bolt in the case and remove the 3 oil filter cover screws in the cover. While waiting for that I decided to take a look at the crank shaft from the 71 CL450 as the crank from the the 72 CB was missing a complete set of center roller bearings. I started by removing and bagging all the bearings and visually inspecting bearing surfaces which look OK as far as I can tell. I cleaned the centrifugal sludge traps next to the center bearings and got a lot of crud out of them but even though I have read @boddy thread "Crankshaft Cleaning" I admit to being a bit confused on what I should do to clean the crankshaft properly as the thread kinda jumped over to K0 cranks which appear to be quite different then the later models. Without pressing the crank apart what is the best method of cleaning the crank sludge traps that members have found? I appreciate everyone's experience and suggestions. The crud stuck on the magnet is probably about half of what I got got out of the grooves by the center crank bearings. I also used boddy's suggestion on making a scraping tool.


IMG_4435.JPG


IMG_4430.JPG
 
The hole from the trap into the crank pin is next to be dug/reamed out. Stand the crank vertically on end and fill the trap with solvent, hopefully it will rinse through the big end rod bearing.
 
ballbearian said:
The hole from the trap into the crank pin is next to be dug/reamed out. Stand the crank vertically on end and fill the trap with solvent, hopefully it will rinse through the big end rod bearing.
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Sounds good. I may have to set up a cleaning tank if it doesn’t rinse through. I also need to measure the journals and the piston rod per the FSM.
 
I flushed mine by pouring solvent from into the small gap on the con rod pictured below, thinking that the larger exit through the hole near the sludge traps would allow more stuff to flush out.
conrod2.jpg
 
boddy said:
I flushed mine by pouring solvent from into the small gap on the con rod pictured below, thinking that the larger exit through the hole near the sludge traps would allow more stuff to flush out.
View attachment 33820
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If I can figure out a tip that would hold pressure when pressed into that gap it would probably work better. Did it seem like you had a good result?
 
I am currently sitting on the deck drinking a beer and enjoying a cigar and letting my mind free range a bit. My biggest limitation is space or I would invest in a parts washer. I can’t justify having the shop I would like built that would house all he equipment I would like.
 
Justification? Que es eso? Space, I can understand. They have simple folding ones, or you can make them really easily out of a folding table and a mortar mixing tray, then just set up on the driveway.
 
A 5 gallon bucket for the crank and hung high aux fuel tank for solvent/gas. Flexible tubing to jam in the trap hole, could even use compressor air there. Either direction should work but the big end isn't sealed so not much pressure going back to the radial drillings in the pin. If nothing comes through then the crank must come apart.
 
EzPete said:
Justification? Que es eso? Space, I can understand. They have simple folding ones, or you can make them really easily out of a folding table and a mortar mixing tray, then just set up on the driveway.
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By justification I meant for the actual shop I would like with a lift for working on the cars and space enough for a a large air compressor, parts washer, media blast cabinet, ect ect.... I actually have a large plastic container I am using as a parts washer outside so could just buy a proper pump that is safe for solvents and it would be fine. I hate taking a car to the dealer or a shop as I have always done my own work and it annoys me when something is not done right or the cost ends up much more than the quote. Regretfully I find I am not as able to crawl under a car or truck for most of a day pulling a transmission or a gas tank to get to the fuel pump or a myriad of things I used to consider routine. This getting older is not all it was cracked up to be. :cautious:
 
RobMan said:
If I can figure out a tip that would hold pressure when pressed into that gap it would probably work better. Did it seem like you had a good result?
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I basically used one of those plastic syringes filled with solvent to guide the fluid into the gap. I'm not sure how you would get a good enough seal to be able to increase the pressure. As far as I could tell there was not much in the way of crud coming out of the big end bearings.
 
boddy said:
I basically used one of those plastic syringes filled with solvent to guide the fluid into the gap. I'm not sure how you would get a good enough seal to be able to increase the pressure. As far as I could tell there was not much in the way of crud coming out of the big end bearings.
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The bearings are mostly too loose to plug. It's the crank pin that gets plugged and if so, then no soup for you.
 
RobMan said:
By justification I meant for the actual shop I would like with a lift for working on the cars and space enough for a a large air compressor, parts washer, media blast cabinet, ect ect.... I actually have a large plastic container I am using as a parts washer outside so could just buy a proper pump that is safe for solvents and it would be fine. I hate taking a car to the dealer or a shop as I have always done my own work and it annoys me when something is not done right or the cost ends up much more than the quote. Regretfully I find I am not as able to crawl under a car or truck for most of a day pulling a transmission or a gas tank to get to the fuel pump or a myriad of things I used to consider routine. This getting older is not all it was cracked up to be. :cautious:
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You forgot a dishwasher and oven but not for food.
 
ballbearian said:
The bearings are mostly too loose to plug. It's the crank pin that gets plugged and if so, then no soup for you.
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For the crank pin I used @jensen's trick of taking the metal cable (in my case an old bicycle cable) and splaying the end to form a little wire brush and running that through the crank pin hole followed by flushing from the con rod gap. The hole in the crank in was clean and nothing came through from the flushing of solvent.
 
ballbearian said:
The bearings are mostly too loose to plug. It's the crank pin that gets plugged and if so, then no soup for you.
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If I had too could I have the machinist drill out the plug and clean the pin out and then have a new plug pressed in without disassembling the crank? IMG_4436.JPG
 
RobMan said:
If I had too could I have the machinist drill out the plug and clean the pin out and then have a new plug pressed in without disassembling the crank?
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Sure, but the radial drillings from that bore to the surface (and bearings) of the pin are even smaller. G-man had posted some pics of plugged pins in the long thread on this subject (I forget who started it).
 
ballbearian said:
You forgot a dishwasher and oven but not for food.
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Funny you say that - the house next door to me is in the process of being flipped and they’re about to tear out the kitchen - I was going to offer to take both of those items off their hands to use the dishwasher as a parts cleaner. Hadn’t thought about the oven
 
Sounds like I have a plan, I will try soaking and flushing solvent through the crank pin area and if I see that it is not working I can go next step and have the plug drilled out. I am sure the machinist I use can assist with that at a reasonable price.
 
Maybe after a good soak, hit it with spray parts cleaner with the skinny tube. Just Jane it into that little space
 
Let me add a word of caution though, at least from my early experience with cleaning cranks and solvent - after giving it a good flush, be sure to squirt some oil into the big end rod bearings before letting it sit. One of mine got stiff from rust starting on a well-washed crankpin.
 
ancientdad said:
Let me add a word of caution though, at least from my early experience with cleaning cranks and solvent - after giving it a good flush, be sure to squirt some oil into the big end rod bearings before letting it sit. One of mine got stiff from rust starting on a well-washed crankpin.
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Thank you for word of caution. I have been spraying down with WD40 after I finish clean for the day especially if I have used any brake clean.
 
Have had the the crank soaking in kerosene since Thursday occasionally sloshing the container and spinning the crank in the liquid. As @boddy suggested I was also able to use a syringe with a short length of windshield washer hose to inject kerosene in both the hole in the trap and the gap in the large end of the connecting rod and saw good flow both ways. There is obviously a good amount of crud in the crank though as after the first day I tipped the container to one corner and poured off the kerosene into a jug with a shop cloth as a filter being careful to keep most of the crud in the corner. A magnet gathered up a large pea size clump of metallic sludge and the shop rag caught a light sprinkle of aluminum bits. Planning on soak and repeat for the next few days to see how much crud comes out. I also laid out both sets of the shift fork mechanisms and sorted out to one set using the best parts of both.

IMG_4439.JPG
 
Still have the crankshaft soaking and periodically flushing and then straining the debris. Getting smaller amounts of metallic particles sticking to the magnet and lesser amounts of aluminum bits as well. I did find an inexpensive option for a pump for my homemade parts washer and it was hanging on my tool peg board in the garage. I am using the harbor freight battery powered transfer pump which works great for my needs. Not as handy as an actual parts washer but gets the job done and the tip of the hose is flexible enough to push into small spaces and see the flow through the openings in the crank pin.

 
Different topic but is there is there any info available that shows the wiring harness connector pin out Information i.e. which color wire goes to which pin number at a connector. I have the wiring diagram in the FSM and color copy I downloaded but they don't show that info. The reason I ask is I was taking a look at the stator to bench test it and the wires are so bleached out it is hard to tell what the colors are. I believe they are supposed to be Yellow Pink and White and I think I have them figured out by shades of grey but the pin number info would be helpful.
 
RobMan said:
Different topic but is there is there any info available that shows the wiring harness connector pin out Information i.e. which color wire goes to which pin number at a connector. I have the wiring diagram in the FSM and color copy I downloaded but they don't show that info. The reason I ask is I was taking a look at the stator to bench test it and the wires are so bleached out it is hard to tell what the colors are. I believe they are supposed to be Yellow Pink and White and I think I have them figured out by shades of grey but the pin number info would be helpful.
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I had the same problem. You can find the info here at post #9
 
RobMan said:
I believe they are supposed to be Yellow Pink and White and I think I have them figured out by shades of grey but the pin number info would be helpful.
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Another way to distinguish the pink, white, and yellow stator wires is from resistance measurements: W+Y is largest, then Y+P, and W+P is the smallest.
 
Also be sure to check all stator wires to ground. There should be no connection. If there is, that stator is defective even though the resistances stl360+450 noted are correct.
 
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