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Discussion Starter · #1 · (Edited)
Hi,
I have a Sprint ST 2002 model, occassional use, always garaged and only 6000 miles

Recently chain appeared very slack, clamp bolt very tight
Locally MOT'd and chain adjusted with difficulty to pass MOT
Chain slack again within 100 miles
Could chain adjuster have seized or is it likely bolt has stripped thread
Any ideas please

LesCar
 

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Chain adjustment

my manual for my 2002 ST targets 1.5" of chain slack while on the centerstand. (1.4-1.6")

That really seemed loose, until I got her off the centerstand and onto the sidestand....not much slack at all. I wouldn't torque the cinchbolt more than the manual calls for.....you'll ruin the swingarm.

---Charlie
 

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Here is a picture of what happens when the pinch bolt comes loose:



If the adjuster seizes, you can not turn it.

Like Charlie says, do not overtorque that pinch bolt. Replacing the swingarm is a huge pain.

Cheers,
-Kit
 

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Possibly what's happened

Hi,

this sounds very similar to something that happened to my 04 about 3 years ago.

I adjusted my chain and found that after a ride my rear sprocket was as far forward in adjustment as it could go. I thought that I hadn't tightened correctly, but after investigation, and removal of the pinch bolt I discovered that the bolt had siezed onto the aluminium thread in the swingarm

I could tell this from the turn and a half of aluminium I had to pick out of the bolt thread :eek:. this meant that the light torque setting that is recommended was doing nothing in terms of making sure the adjuster was pinched up. So the eccentric was just spinning back round.

After consulting on this forum (can't find the thread now as it was on the old incarnation of the forum) I cleaned the bolt up and ran it up the thread from the underside of the swing arm, and then did the same from the top, using the bolt to clean up the thread. The bolt is quite happy in the thread again, but I now ignore the torque setting recommended. After discussing it with a tech at the garage, he said (tighten it up until you can see the slit between the two parts of the swing arm close up. This is more than the setting, but the thread and the bolt are quite happy with this treatment and I've had no problems with it in 3 years.

Alternatives offered by the group were to tap the thread out to a larger size and use a bigger bolt.

Use a thinner bolt that would pass all the way through the swing arm and fasten with a nut and washer to get it to clamp.

Put some form of thread insert in.

Incidentally you don't actually need to take the swing arm off to re-tap... a careful hand tap is possible with the wheel removed!

Rexx
 

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BTW: My pic there is from when the adjuster was loose in spite of being torqued to 55Nm, presumably due to corrosion between the bolt and threads. I spent ages trying to find a replacement for the pinch bolt in stainless steel, only to find out that the Triumph part is now stainless.

Cheers,
-Kit
 

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The bolt is quite happy in the thread again, but I now ignore the torque setting recommended. After discussing it with a tech at the garage, he said (tighten it up until you can see the slit between the two parts of the swing arm close up. This is more than the setting, but the thread and the bolt are quite happy with this treatment and I've had no problems with it in 3 years.
Rexx
Rexx,
I don't mean to defecate in your messkit, but that sounds like a possibly risky way to tighten a cinch joint. I am a mechanic, and I have seen, cursed, and have had to deal with overtightened cinch joints numerous times on many kinds of equipment. If the ears are tightened until they touch, you stand a real danger of stretching or deforming those ears, which the bolt is applying force to, to close up the bore. I've read a good number of your posts, and I'm pretty sure that you're more careful than that. Case in point is how you noticed that your threads were fouled, and you weren't getting the joint tight. You can get away with bringing the outer edges closer together to get it tighter, but you surely don't want to bury the inside and outside edges together. This metal will deform and stretch. Then you've got serious problems. I can see if a previous owner has overtorqued a cinch joint, and you have to give it more torque to hold. But you really have to be careful, because once the ears are bending in, it begins a loosing battle: it always takes a little more, then a little more to keep it tight. Then it's stretched too far, and you're screwed.
Please be careful with all the cinch joints on these bikes. I would never tighten them any more than what you need to keep the shaft secure.

I just don't want to see anyone tear one of these up if they can avoid it.

---Charlie
 

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Know what you mean CharlieS

I think perhaps I was a little imprecise in my language.

I didn't meant that I pull them together until they are touching. Definitely bad. I tighten up the bolt until I see the gap between the two parts change in width. Loose, it is about the thickness of a credit card.

I forgot to mention I am very generous with the copper slip as each time I adjust the chain I remove the bolt completely and copper slip it. I know this is not good practice on a bolt that should be torqued down, but as I am not setting it to a specific torque, I would rather have the copper in there preventing the 'weld' and it also is rather good at showing the gap begin to close!!

Rexx
 

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Welcome

Hi,
I have a Sprint ST 2002 model, occassional use, always garaged and only 6000 miles

Recently chain appeared very slack, clamp bolt very tight
Locally MOT'd and chain adjusted with difficulty to pass MOT
Chain slack again within 100 miles
Could chain adjuster have seized or is it likely bolt has stripped thread
Any ideas please

LesCar
Hi Lescar, welcome to the Sprint forum:welldone:

Looks like the guys here have you all fixed up good, we have a lot of friendly & very helpful people on this board.

Don and ask all our new peeps Les to please read our forum stickies just as a matter of course:)

Cheers and enjoy the forum
DaveM:Helmet
 

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I think perhaps I was a little imprecise in my language.

I didn't meant that I pull them together until they are touching. Definitely bad. I tighten up the bolt until I see the gap between the two parts change in width. Loose, it is about the thickness of a credit card.

I forgot to mention I am very generous with the copper slip as each time I adjust the chain I remove the bolt completely and copper slip it. I know this is not good practice on a bolt that should be torqued down, but as I am not setting it to a specific torque, I would rather have the copper in there preventing the 'weld' and it also is rather good at showing the gap begin to close!!

Rexx
Just a point about the copper based anti-seize. From what I can gather we should be using a Nickel based product rather than copper. Copper and aluminium react to one and other in some negative way I am not sure of. I needed to renew my anti-seize and at the local auto parts shop they had a chart showing the various types of anti-seize and the uses (metals) they could be applied too. Copper was definetly shown as being not able to be used on aluminium products.
 

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You might be correct about that, but I do know that Triumph used it on our bikes at the factory.
 

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Discussion Starter · #11 ·
Hi,
I have a Sprint ST 2002 model, occassional use, always garaged and only 6000 miles

Recently chain appeared very slack, clamp bolt very tight
Locally MOT'd and chain adjusted with difficulty to pass MOT
Chain slack again within 100 miles
Could chain adjuster have seized or is it likely bolt has stripped thread
Any ideas please

LesCar
Thanks Guys for info and advice

LesCar
 

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Wow! This is just wrong........first I bust Rexx's tightening of the cinch bolt ( I misunderstood what he was saying as to how he was tightening it), and now he's getting it over the antiseize!
Antiseize on that bolt is the smart move, given the bolt location and the tendancy for the threads to foul. Also, Rexx's observation of the threads fouling, resulting in the cinch joint not tightening up, and his method of addressing that problem were and are dead nuts correct. Not that he needs me to tell him, he knows what he's doing. :)

---Charlie
 

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Rexxy said he did the described repair three years ago and all has been well since, so it must be okay. But I would not go as far as saying that he is dead nuts correct in his repair. Cleaning the threads and installing the bolt to factory specs should have been the first choice. If that failed, any of the suggested alternatives would have been acceptable.

In essence he now has a threaded joint that was been damaged to some degree, possibly from over torquing, and has installed a fastener in it and purposely over torqued it. :confused:

But, I guess three years has to count as a good test. :D

As to guesstimating the amount of pinch, seems it would be better to measure the gap unloaded, then tighten it until it closes one or two thousandths. I would guess that gauging visible movement/closure leads to excessive clamp up.
 

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Getting What Wrong ????????????????

Wow! This is just wrong........first I bust Rexx's tightening of the cinch bolt ( I misunderstood what he was saying as to how he was tightening it), and now he's getting it over the antiseize!
Antiseize on that bolt is the smart move, given the bolt location and the tendancy for the threads to foul. Also, Rexx's observation of the threads fouling, resulting in the cinch joint not tightening up, and his method of addressing that problem were and are dead nuts correct. Not that he needs me to tell him, he knows what he's doing. :)

---Charlie
What's he 'getting' over the anti-seize, no one is saying that it is not a smart move to apply anti-seize to that bolt/thread. No misunderstanding on my part!
 

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Rear Wheel making a noise after chain adjustment

I have have the 1999 ST for a month or so. I am going on a two week trip soon so thought I should adjust the chain for practice. It also needed tightening. I managed to get the c-spanner in the correct place eventually.

I tightened the cinch bolt back up to the correct torque. I decided to inspect my rear tyre. When turn the wheel backwards there is a noise coming from what soundshe hub. Turning the wheel forwards does not seem to be a problem.

Is the cinch bolt tight enough?
 
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