Stuck clutch

Stuck Clutch.

I recently had a stuck clutch with the bike, it's a problem all motorcycles are susceptible to and usually if left unused for a while or if a motor oil like synthetic 10W 40 that is designed to be used in cars is used by mistake. This oil contains other additives which apparently does not work well with a clutch in a wet clutch scenario and over time can cause trouble. Of course a proper 10W 40 '4 stroke' motorcycle oil should be used. I'm assuming the previous owner used the correct oil type, however maybe it would make sense to do your own fresh oil change when purchasing a bike anyway, regardless of how 'full' it is. The bike was stood around for a little while as well over summer while spending a lot of time visiting sick relatives in hospital but, again I wouldn't of thought it long enough to cause the problem, however it was what it was and I had a stuck clutch.

It was a problem that was easily fixed, just a bit fiddly and a touch time consuming. All I needed to do was drain the oil by removing the sump bolt underneath, then remove the clutch cable from the actuator arm, remove the kick-start then open / remove the crank case to expose that part of the engine. Then you need to remove the clutch basket (there's a cir-clip to remove once you've removed the bolts & springs & took apart the front thrust plate assembly), open it up, remove the clutch plates and rings and clean them up with white spirit or petrol on a paint brush, then dry them with the airline or a dry rag and put it all back together and fill with fresh oil.

HOWEVER, to remove the clutch basket you need to remove the 'oil filter rotor' which over hangs the clutch basket and I couldn't get the 3 screws out myself without rounding the screws off. Using a blow torch on the area they are screwed in, so it expands to help loosen the screws always works wonders but was out of the question because of the proximity to the petrol tank. Rounding the screws off would be very bad as it wouldn't be able to be removed at all without destructive means of the oil filter rotor which then would have to be replaced with a new one. I had no choice but to take it to a mechanic shop with the means to remove the screws.


 I had also since discovered that a brand new set of clutch plates for Honda CG / CB or FMI 156/ 157 were about from only £7.00 on eBay if you have a look through the list. Although when cleaned the current plates would be fine, and another set I have in a clutch basket I bought from a breaker just in case the problem was much worse would also be fine (none were actually worn out), for the sake of seven quid I might as well replace the plates for new ones while I have the chance. You don't open the engine up like this all the time and replacing with new ones now means I won't have to replace due to wear for a longer length of time. So I asked the mechanic to fit the new plates before putting it back together for me.

In the end we have a working clutch again. But it's cost me for the sake of  3 oil filter rotor screws!

Clutch considerations.

Like mentioned before, in case it was a worse scenario than the 'stuck clutch' I purchased a cheap replacement whole clutch basket complete with plates and rings, from an online breaker. Coming from a 2013 XTRS. Now the basket, although able to fit (the dimensions are all the same for 156 / 157 FMI clutch baskets and are interchangeable engine to engine) there are a few differences. For a start it had a five bolt thrust plate opposed to the four bolt one already on the bike. This wasn't the problem however, the bearing was smaller and I only had a bush sleeve (known as the rod spacer on the parts page) to fit the lager bearing in the original basket, so the mechanic had to use that basket again. Luckily nothing was wrong with the old basket anyway. But it's something to consider. And something breakers should supply you with (the rod spacer to fit that baskets bearing size for 156 FMI engines) or indeed if your buying a general 156 / 157 FMI clutch basket new that's not necessarily labelled for the XTRS.

If you need to clean your plates and rings remember to pay attention to how they are assembled. There is a ring between every plate. Make a note of the correct order for when you reassemble. If you're not sure, we live in an age where you can take a photo on our phones of something for future reference. All in all it is a do able job, unless you get the same trouble I did with the 3 screws in the oil filter rotor. Believe me it's not worth knackering the screws, take it to a mechanic that has to deal with this stuff all the time. The only other option would be to get an angle grinder and cut the oil filter rotor where the screws sit, then buy a replacement oil filter rotor. If you manage to get the screws out I see about getting some decent steel replacements the same size and thread. I can't see any replacement screws on the CMPO site at a glance in any case.

CMPO clutch parts:

http://www.chinesemotorcyclepartsonline.co.uk/search.php?name=xtrs+clutch#results