Triumphrat

toonyank · 09-22-2009, 01:00 AM

Has anyone ever experienced chain tension slip?

With the single sided swing arm I've adjusted the chain tension twice in 2 weeks and even though I've torqued the clamp bolt to the recommended 55Nm it just keeps loosing tension.

Has anyone experienced this kind of slip?

kevin_stevens · 09-22-2009, 01:18 AM

Quote:

Originally Posted by toonyank

Has anyone ever experienced chain tension slip?

With the single sided swing arm I've adjusted the chain tension twice in 2 weeks and even though I've torqued the clamp bolt to the recommended 55Nm it just keeps loosing tension.

Has anyone experienced this kind of slip?

Not with my Speed Triple, Sprint, or my Ducati 748 with a similar adjustment setup.

When you say "it keeps loosing (sic) tension", do you mean the clamp bolt is backing off, and then the adjustment slips; or do you mean the adjustment slips while the clamp bolt stays torqued?

If the former, try blue Loctite. If the latter... no real suggestions. You'll probably have to take the hub apart and find out what's wrong.

KeS

toonyank · 09-22-2009, 01:51 AM

No it's the latter. It would take some kind of vibration to shake 55Nm. I'll have to strip it down. It seems to only slack off so far and not so much that it would jump teeth. I would say between 1.5 and 2 times the maximum movement but enough that you can here it when slowing down.

Martin_R · 09-22-2009, 04:29 AM

Maybe the chain on your bike is on it's last legs? Thats when they usually start streching fast. Doublecheck that you are not overtightening chain - there should always be some slack still with rider on board. Never should the chain be tight like a piano wire when rider compresses suspension a bit.

Second guess would be that one of the plastic chain rubbing guides on the swingarm has worn through.

Other than that, I do not see how the eccentric adjuster itself would rotate on it's own if the clamp bolt and threads on the swingarm are still OK. There should not be any major rotating force on the eccentric as it is separated from the swingarm by bearings. The bearings would have to be shot for the actual engine torque to make it's way to the eccentric.

How many miles since the last regrease of the axle bearings? How many miles on bike?

toonyank · 09-22-2009, 11:27 AM

18K on the bike and chain. Chain and sprocket look good. It's a mystery?

Joemomma · 09-22-2009, 12:00 PM

Did you actually measure the chain? At 18K it's probably close to the end of it's life...

1. Remove the chain guard from the swinging arm.
2. Stretch the chain taut by hanging a 10-20 kg (20-
40 Ib) weight on the chain.
3. Measure a length of 20 links on the' straight part
of the chain from pin centre of the 1st pin to pin
centre of the 21 st pin. Repeat the test at various
sections of the chain to establish an average
reading. This is because the chain may wear
unevenly.
4. If the length exceedsthe service limit of 321 mm,
the chain must be replaced.
I

toonyank · 10-28-2009, 11:12 AM

Well after the 4th time of adjusting the chain tension I'm sure it's somehow slipping and the clamp isn't holding.

I haven't measured the chain but it would have snapped by now if it stretched that much over 4 times. I'll have to strip it and figure out how it's not clamping right.

wabill · 10-28-2009, 12:34 PM

"Anyone know where there is a good online supplier of parts like gear shift rubbers etc... Mine is shot and I don't know a good supplier."

Let me get this straight, you've worn out the gear shift peg rubber yet you won't measure your chain to see if it might of stretched?

toonyank · 10-28-2009, 12:42 PM

Quote:

Originally Posted by wabill

Let me get this straight, you've worn out the gear shift peg rubber yet you won't measure your chain to see if it might of stretched?

Get it straight then. I never said it hasen't stretched. It's an '03 probably the original. What I said is it hasen't stretched as much as I have made adjustments. The number of times I have adjusted this it would have stretched about 4 inches. It would have snapped by now.

In less than a week I go from the normal 30-40mm of travel to about 100mm and this has happened about 4 times.

PhilM · 10-28-2009, 04:27 PM

1. Are you measuring that 30-40 mm of travel with someone on or off the bike.
The slack needs to be set with someone sitting on the bike.
2. I would not be afraid to go tighter on the clamping nut than 55nm.