Stainless Steel Chain Adjuster Bolts - Recommendations Please?

Racebolt?
Stig Fasteners?

 

stig fasteners use them all the time never any issues

 

with a 13 mm head can you get a spanner on it and turn it well enough to adjust it ?

 

Standard pitch (1.25mm, coarse) m8 bolts with 13mm a/f heads work fine. A normal 13mm open end spanner works, as long as you're careful. I bought a couple of cheap spanners and ground the outsides down, to give better clearance.

 

I just filed a the head of 13mm bolt down down to 10mm it takes a while but works well.

 

To confirm what others have said.

The pitch is 1.25mm, and a 13mm head doesn't foul on the side of the arm.
You get a little less movement with each swing of the spanner, but it works.

It's what is fitted in the image below - Yes I know the locknut is backed right off in this image.

Nasher

 

I'll just throw something in here, does it really need to be 70mm? I was taking my swingarm off last night and it took ages to take the bolts out, would a 55mm not do?

 

From memory, I think 55mm would leave very little thread in the body of the arm if you let your chain get to the point of needing all the adjustment available on the arm. Not that I'm suggesting in any way that it would be acceptable to do that.

Nasher

 

Yeah, I wasnt sure if it would be ok with a 55. My chain is pretty good not done that many miles so I guess I have them wound in quite a bit.

When I first fixed up my bike I got new OEM bolts from Ducati. They are a right PITA to remove if they do get seized so I use a little copperslip on them. The nut keeps them locked.

 

Hi James,

I've not been on here much lately. These bolts are a pain! I got mine drilled out as you are doing. Both my bikes have 13mm bolt heads - working fine. I did use 70mm - it will be that length for a reason. I filled the swing-arm with expanding foam. My idea was to stop internal condensation which was probably responsible for the corrosion. Not sure if it will be a good thing.

Have you started a thread? I will watch with interest.

I am about to start restoration number two - on supersport number 200.

Phil

 

Sorry to resurrect an old thread, but I have just run into this problem.......so a few questions....
1. How deep is the threaded hole in the swingarm into which the chain adjuster bolts are screwed?
2. The bolt will screw in (albeit stiffly) but as it is screwed out (to bring the axle to the midpoint on the marking) it gets stiffer and stiffer.....I've tried working a bit of penetrating oil into the threads by winding the lubed bolt in and out but with apparently limited success (hence question 1!).
3. If it does prove impossible to wind out fully, I was thinking of cutting the head of the bolt off, cutting a slot in the shank and screwing the remains of the shank in, then cleaning thr hole out with a tap. This will obviously lead to the liberated bit of bolt rattling around in the swingarm. Are there any apertures via which it could be extracted? Or is it a cut and shut job?
4. If push comes to shove and it has to be drilled out, how is the threaded hole in the swingarm made good? An insert? Or can it be made good without damaging the threads (too much)?

As ever, your help and advice appreciated!

S23

 

if the thread in the aluminium is damaged it could be repaired by using a helicoil insert or similar insert
which would be stronger than the original thread if it is just in the aluminium
not sure but a bit of careful heat on the aluminium and penetrating fluid as you work the bolt might help .probably use something like a hot air heat gun not a blow lamp so as not to do serious damage
the aluminium should expand faster than the steel bolt allowing free movement maybe a bit of freezew spray on the bolt to make it contract as well

 

I think number 3 is a brilliant bit of lateral thinking! Of course you'd want to be able to screw it all the way in as far as it will go, with the head still on the bolt, before risking cutting off the head and and doing the job of consigning it to rest forever inside the swinging arm. I can't believe that it would do any harm in there, if it doesn't in some way obstruct the use of a new bolt after cleaning up the threads as you suggest.

 

Yes, I think you mean screw it out as far as it will come before cutting the head off and screwing it back in again? As this will mean the bit of bolt that will be banished will be as short as possible?

I did think also of drilling a small hole (2/3mm in the side of the swing arm just forward to the bit where the bridge is welded on so I could get the thin plastic tube from a penetrating oil spray in there and lube the bolt from the back, as it seems that the bit of the tensioner bolt that protrudes into the cavity of the swingarm has corroded, leading to this problem with removal - but others have councelled against this, owing to the possible creation of a stress riser, so I think I'll leave that one alone.