Clunky Transmission

[Richie B]

When changing gear (up and down in all gears) I have noticed the noise is getting increasingly worse with an added jolt. This is obviously not normal and, as a complete mechanical novice:

1. Any ideas what's wrong?
2. Is is repairable or do I need a new gearbox?
3. Are new gearboxs expensive (incl fitting)?
4. Where's the best place to get a new gearbox?
5. Am I asking too many questions?

I have noticed this problem since the Salisbury Plain session. And I still haven't managed to get my bike clean..........

........ would appreciate any comments you might have. Cheers.

[Maverick]

Richie,

How tight is your chain and is it set correctly?
Have you checked the wear on your sprockets escepcially the front one. Your bike is low mileage if I remember correctly and hopefully not the gearbox.

If one of the sprockets are worn or lost a tooth it can give a jolting effect, have you still not cleaned all the mud and crap from the chain and the front sprocket housing? If not do so and relube the whole business.

I would start with the obvious mechanical stuff first before moving onto the more ermmm how could one put it expensive stuff. Do you not work close to me in the city (holborn), we can always arrange to meet after work tomorrow evening and I can have a quick look. Might just spot something you have missed.

[iswoolley]

Might also be worth checking the clutch cable adjustment. It could be that the clutch isn't disengaging during shifts, hence more clunk than normal. Just a thought.

[Richie B]

Hey Maverick, hope you're well:

The Chain and sprockets are almost new: About 1000 miles/2 months old. I haven't checked that the front one was replaced but the mechanic 'said' it was and I've no reason to disbelieve him (it all comes as a set I believe).

I gave the chain a good going over after the Plain so it should be OK. I will check the chain again but i have heard different opinions on the slack. Mr Haynes says 35-45mm whilst on the side stand and other people have said that it should be checked whilst sat on the bike? What d'ya reckon? After seeing Colin's (very) slack chain it's made me wonder what the real deal is.

Would be good to meet up but i'm on a course in Horsham this week. Can't you make the Lakes trip? I'm missin' your screen

ISWoolley - when I pull the clutch in when cruising along normally (without releasing back the throttle) the revs rise as expected so I assume the clutch is disengaging. Cheers though.

Thanks for the ideas. If it saves me on a garage trip, keep em coming....

[Richie B]

Oh yeah, the bike's done 21K. Very little service history though: The previous owner claimed to have done the service and maintenance himself. Hmmmm

[Dilbert]

Maybe really dumb, but have you got any oil in the box? I've had a few Honda's that seem prone to this when the oil gets a bit low, kinda early warning clunk

[Richie B]

Yep, checked it this morning. It was changed when the chain+sprockets were replaced so it shouldn't be too thin yet. I have ordered a new oil filter to do another oil change this weekend 'just in case'. Can't do any harm.

[Maverick]

Richie the chain should be very lose mate, Yen posted something on here about the correct way to check it. The fact that his bike has done over 120k miles will go with that.

Will search for the topic and post it here. Think it was about 70mm play at the mid point of the chain. Mine is set so lose if you check it from the side it seems to hang.

[africatijn]

You can also check www.atic.org

Has a very good description on how to check the chain.

Cheers,
T.

[Richie B]

Well I've slackened off the chain a bit and done an oil/filter change. Doesn't seem to be much difference. I think i'll let the more experienced @ riders take a look up at the Lakes next weekend. Perhaps it's normal & i'm just not used to it.

When I took the bash plate off I noticed that I had half of Salisbury Plain lurking underneath. Potatoes growing and everything......

I've recently bought some Diadora boots which are still dead stiff and are affecting the gear-change. May have something to do with it. Perhaps I need a longer gear peddle to accomodate my size tens?