15 replies to this topic

[openroad]

hi all. think i may have mention this issue before but can't find where it it. i know the mk1 850 has a clunky gear box especial changing to 2nd. my bike don't clunk it grinds into gear. i put it in to 1st no problem but when i change to 2nd and then to 3rd i got to make sure i'm not going to fast and i hold the clutch in for a fair bit of time and allow the revs to drop right down before changing other wise it it grinds into gear. it don't do it changing to 4th and 5th. i've put the bike on my padock stand and tried going through the gears and it didn't grind once. i've change the cush drive rubber the chain is tight enough. 25 mm play up and down. i don't know if this is a part of it but if i'm in 3rd or forth and give it a bit of stick it feels like something slips on the drive chain it's not the clutch because i don't i don't hear or see th revs rise it only happens momentary. and don't happens all the time. i thought it was the rear wheel spinning up but its a bit more vicious.

[Studley Ramrod]

Grinding into gear and gear slipping might be more than one problem if it's not the clutch.

Might be worth having a good look at the front drive sprocket for starters, take the nut & sprocket off and check the splines.

I'm assuming the sprockets' teeth and drivechain are in good condition ?

Might be worth investigating the clutch area, hard to say what's causing yer problems really though.
Have you tried reducing the clutch cable freeplay ?

Could also check the cushdrive rubbers and the sprocket carrier bearing, I had a bearing loose on my mk1 and it wore out the carrier.

Also had a snagging clutch cable that only showed up when I was at high speed and trying to go even faster.

[LeoD850]

Not sure if this would cause the grinding , but on the MK2 the chain tension is between 40mm and 50mm and I think it is 40mm on the 900. You might check what it is on the MK 1 !!

[openroad]

Not sure if this would cause the grinding , but on the MK2 the chain tension is between 40mm and 50mm and I think it is 40mm on the 900. You might check what it is on the MK 1 !!

the chain is starting to stretch a little more regular so could do with a change just been putting it off till i have to get the rear tyre change so i can do it all in one go. back sprocket looks ok but best to do it all the same time. not looked at the front yet. the clutch seems ok when i had a look a couple of months ago, no ridges on the basket.

[Margus]

the chain is starting to stretch a little more regular so could do with a change just been putting it off till i have to get the rear tyre change so i can do it all in one go. back sprocket looks ok but best to do it all the same time. not looked at the front yet. the clutch seems ok when i had a look a couple of months ago, no ridges on the basket.

When chain is too tight (as you said 20-25mm on your bike), then it stretches out wery quickly. 3VD chain free play should be about 40mm

[mh1848]

When chain is too tight (as you said 20-25mm on your bike), then it stretches out wery quickly. 3VD chain free play should be about 40mm

the manual gives free play of between 40 and 50 mm for the 850

[openroad]

thanks for the heads up on the chain play.

[openroad]

i don't know if this means anything to anyone. i normaly let the bike warm up then go out for a spin but i was running late so i just started and rode. and there was no grinding clunking untill engine warmed up. i've got 10 40 oil in it could a thicker oil help. i did a oil change about 2 months ago so i know the oil in it is still good. can you get a oil that works better at higher temps if so what should i try.

[openroad]

anyone got an idea what my problem is

[SteveK]

anyone got an idea what my problem is

I wonder if the clutch is dragging when its warm (hot). Only way to tell is to get to the gear clunking stage and stop the bike in 1st or second gear (on a level road). With the clutch pulled in try to push the bike along the road. If the clutch is dragging you'll find it hard to push. If the clutch is dragging you'll need to investigate things like spring length, plate warping etc.

Good luck

Steve K

[openroad]

thanks stevek i'll try that.

[celticbiker]

A above but I would also suggest trying a good oil like castrol power 1(semi synth only though) and if you haven't already, a new oil filer.

[openroad]

i service the bike a few months ago. it's always been like this since i've had the bike. the bike belonged to a youngster and he said to watch about the front end will pop up which is making me think he's been slipping the clutch alot could this cause the friction plates to warp. there is no sliping when i ride it even if i'm in 5th and pulling hard, think i might just change the clutch springs and put proper bike oil in it instead of wilkos oil.

[TYREDNGRUMPEE]

anyone got an idea what my problem is

Yes.

Your description of the symptoms (gear grinding between first and second and nowhere else) points to wear in the components that select the gears sequentially, that is, any or all of the following.

1. Selector barrel/ worn channel
2. Selector fork/ worn fork faces, bent arms, worn selector dog
3. Channels that the selector forks run in on each gear wheel (less likely)

If the previous owner was an accomplished wheelie merchant,or a di*k(not related I hope!), then he would've been banging the bike into second without using the clutch and getting it wrong.
The wear and or bending will be minute, but it's exactly where you and I want to change briskly into second under load in normal use.
Cold engine oil will help.
Given how touchy the TDM is with oil, I don't think using anything else apart from the usual will help in this instance.
I would experiment with drive chain slack to see if this improves matters, as it did with my EXUP, esp if you are large or carry loadsa luggage.

Otherwise the good/bad news is that you'll have to go inside to locate the issue and it may not be obvious. Sorry.
I would adopt a riding technique that skirts around the problem at 1^st and 2^nd, be gentle and deliberate about changing up for now whilst congratulating yourself for the money saved and time spent riding this Summer. A winter project perhaps

[openroad]

thanks for the replay TYREDNGRUMPEE. i had a feeling it was going to be this. this will be the second bike i've had thats had gear problems. my last bike was a zzr 1100 that didn't have a 2nd gear at all and i just dubbled click in to third. i can ride the bike just got to take it gingerly with the gear changes keep revs low. lucky the tdm has enough grunt to pull from low revs. this will be an engine out split the case type of job then. Don't supose any want to earn some cash throught the winter months in wales.

[TYREDNGRUMPEE]

thanks for the replay TYREDNGRUMPEE.

Thank you openroad. All my EXUPs needed gearboxes seeing to as well because of the way they had been treated. Make the most of the Summer then and keep an eye out for a donor motor. Plenty turn up that are already half split with damaged cranks and heads. You could snap one up fer littles and start on it before dismantling your own bike.
That is what I'd be doing.