Bainbridge
New Member
Hi all
Here she is when I bought her in January, having stood for 23 years
Here is what I have done so far:
Replaced snapped throttle cable
Degunked carbs and new carb gaskets
Cleaned inside of fuel tank
Replaced fuel tap gaskets
Replaced fuel lines from tank to carbs
Replaced battery
Replaced rear mudguard
Replaced spark plugs
Unseized front brake caliper and new front brake cable
Replaced faulty front brake stop switch
Fixed speedo
Fixed rev counter
Also bought a few shiny bits but more of these are needed.
Also, as you will see below, I have gone against the ethos of a faithful restoration after I was unable to source replacement exhausts and bought a custom made 2-1. Sorry folks, I hope that I have not put too many noses out of joint with this.
Also, I am very much a beginner with engine work. I have serviced our cars for 20 years and as time has gone by I've tackled larger jobs, but I'm not a mechanic and apologies if I use the wrong terminology or not explain things too well.
Of course I will try and clarify and provide further info if needed.
She's running, but off the kickstart because the electric starter hardly turns the engine. She's not running well. It starts first or second kick in the warm with no choke, and initially idles well. Once warmed up the idle deteriorates and I have to use the throttle to keep running.
When the engine is cold the engine seems very solid and revs strongly from idle to 3000 rpm, but once warmed up it hesitates from idle speed up to 3k. Past 3k up to 6k it seems much stronger.
The right cylinder is not operating properly. I did a compression test and dry there is 100psi on both sides. With a wet test, both have 125psi initially but then the right loses compression on successive tests much more quickly than the left.
When the engine was warmed up and idling badly, I removed the spark plug cap from the right spark plug and there was no change to the idle of the engine! I replaced it and removed the left spark plug and the engine died straight away.
I experimented with this at different revs, and above 3k when removing the left spark plug lead the engine does continue to run on the right cylinder, albeit very lumpy, so I determined that both cylinders are getting a spark.
Today I decided to have a good look at her on my day off from work. Using the manual, I removed the fuel tank and checked the valve clearances. They were out of spec but only be a very small amount. Worryingly when I began removing the screws of the generator cover to get at the timing marks, oil began dribbling out of the bottom screw hole! So I drained the oil before removing the cover. The copper coils and the rotor in the middle was covered in oil, so something is amiss here I think.
I checked the points and again, they were a little wider than spec but only slightly, so I cleaned and adjusted them.
After reassembling and refilling with oil, the engine ran exactly the same, but a little quieter which I put down to fresh oil.
I read in the manual that with this twin engine both cylinders fire together. So, I removed the spark plug caps from the HT leads and rerouted the lead serving the left cylinder to the right, and vice versa. Then I reconnected the leads and started the engine, experimenting as before. No change.
Maybe the carbs needs some attention? Both carbs were originally solid with varnish, and I had to completely strip them to get everything cleaned and the passages cleared. I understand that one part of the carb takes care of fuelling from idle speed to a certain rev speed, then other parts of the carb provide fuel as the engine gets faster and demands more fuel. Maybe this needs looking at?
Anyway thanks for reading this long post and any suggestions or comments will be welcome.
Here she is when I bought her in January, having stood for 23 years
Here is what I have done so far:
Replaced snapped throttle cable
Degunked carbs and new carb gaskets
Cleaned inside of fuel tank
Replaced fuel tap gaskets
Replaced fuel lines from tank to carbs
Replaced battery
Replaced rear mudguard
Replaced spark plugs
Unseized front brake caliper and new front brake cable
Replaced faulty front brake stop switch
Fixed speedo
Fixed rev counter
Also bought a few shiny bits but more of these are needed.
Also, as you will see below, I have gone against the ethos of a faithful restoration after I was unable to source replacement exhausts and bought a custom made 2-1. Sorry folks, I hope that I have not put too many noses out of joint with this.
Also, I am very much a beginner with engine work. I have serviced our cars for 20 years and as time has gone by I've tackled larger jobs, but I'm not a mechanic and apologies if I use the wrong terminology or not explain things too well.
Of course I will try and clarify and provide further info if needed.
She's running, but off the kickstart because the electric starter hardly turns the engine. She's not running well. It starts first or second kick in the warm with no choke, and initially idles well. Once warmed up the idle deteriorates and I have to use the throttle to keep running.
When the engine is cold the engine seems very solid and revs strongly from idle to 3000 rpm, but once warmed up it hesitates from idle speed up to 3k. Past 3k up to 6k it seems much stronger.
The right cylinder is not operating properly. I did a compression test and dry there is 100psi on both sides. With a wet test, both have 125psi initially but then the right loses compression on successive tests much more quickly than the left.
When the engine was warmed up and idling badly, I removed the spark plug cap from the right spark plug and there was no change to the idle of the engine! I replaced it and removed the left spark plug and the engine died straight away.
I experimented with this at different revs, and above 3k when removing the left spark plug lead the engine does continue to run on the right cylinder, albeit very lumpy, so I determined that both cylinders are getting a spark.
Today I decided to have a good look at her on my day off from work. Using the manual, I removed the fuel tank and checked the valve clearances. They were out of spec but only be a very small amount. Worryingly when I began removing the screws of the generator cover to get at the timing marks, oil began dribbling out of the bottom screw hole! So I drained the oil before removing the cover. The copper coils and the rotor in the middle was covered in oil, so something is amiss here I think.
I checked the points and again, they were a little wider than spec but only slightly, so I cleaned and adjusted them.
After reassembling and refilling with oil, the engine ran exactly the same, but a little quieter which I put down to fresh oil.
I read in the manual that with this twin engine both cylinders fire together. So, I removed the spark plug caps from the HT leads and rerouted the lead serving the left cylinder to the right, and vice versa. Then I reconnected the leads and started the engine, experimenting as before. No change.
Maybe the carbs needs some attention? Both carbs were originally solid with varnish, and I had to completely strip them to get everything cleaned and the passages cleared. I understand that one part of the carb takes care of fuelling from idle speed to a certain rev speed, then other parts of the carb provide fuel as the engine gets faster and demands more fuel. Maybe this needs looking at?
Anyway thanks for reading this long post and any suggestions or comments will be welcome.
