Hello to all
Being new to hand change gearbox I am unsure if it is operating correctly.
With the engine running pulling in the clutch and putting into first gear I get a grinding of the gears, with a shove it will go in and changing to second is a smooth operation.
With the bike on its stand engine not running I can put into first pull the clutch and spin the back wheel let go of clutch and the drive engages so the clutch seems to be working OK.
Is there some adjustment required?
Cheers for any advice.
Peter
Hi Peter,
I have a Burman 4 speed gearbox with foot control but exactly the same effect. However, only when the engine and gearbox are still cold and then I often start in second gear. I had never opened the gearbox and therefore do not know if the higher gears are synchronized. I think it has something to do with the lubrication. But maybe our experts can say something about it.
Cheers, Thomas
Hi Peter
I can't remember which bike you have but it is important that the clutch is adjusted properly and with the correct lubrication in the primary chaincase.
If its a later clutch with the 6 pocket springs then these should be adjusted so that the clutch lifts uniformly and not on the wonk. Secondly there are clutch stops in the front chain case cover which should be adjusted so that they just touch the outer plate when the clutch is operated, then back off 2 and a half turns. If the clutch stops are badly worn the club sells replacement material on the shop (https://marston-sunbeam.org/sunbeam_shop17/new-stock/291-clutch-outer-case-stop-buttons-rod-for-2.html).
Another point is before you try and start the bike pull the clutch in and kick over, often the clutch will stick if its been left for a period, it should spin with the clutch pulled in. There are more details on adjusting the clutch in the Bruce Main service book and the Sunbeam Manuals that the club sells on the website.
I have also just realised that this topic has been covered before on the forum and there is quite a lot more detail in this thread (http://www.marston-sunbeam.org/sunbeamForum/index.php?topic=453.0).
Graham
Thanks Thomas for your comments much appreciated and Graham also.
My clutch has 6 spring assemblies.
My bike is a 34 model 9 by the way.
Graham I have taken in what you say good info there and will look into your suggestions
Cheers
Peter
Graham
I have attached a picture are the clutch stops located behind the two big locknut either side? I assume they are.
Also I tried kicking it over with the clutch in and it spun freely so the clutch is working. I will attempt to do some checks and adjustments as you said in the earlier post.
Cheers
Pete
Hi Peter
Yes those are the clutch stops, you can screw them out completely and check that there is some friction material remaining.
Graham
Graham ta
I have seen them in the club shop £6 cheap as chips so will most probably get some as spares anyway.
Also I am buying a copy of that book you recommend by Bruce main 👍
Peter