Adjusting a Honda pro-arm (tightening chain)

Hi All,

I'm wondering how many of you have dealt with a honda (bros in my case) pro-arm? Firstly I loosen the pinch bolt. I have a c-spanner which is supposed to do the job of adjusting the eccentric bearing but it does not seem to grab onto any of the ridges on the pro-arm hub....

Am I doing something stupid or maybe I have the wrong size/type of c-spanner. Is this supposed to be an easy procedure or is there a lot of force involved? I read on google groups about just loosening the pinch bolt and then adjusting by trying to rotate the 45mm wheel bolt - any thoughts?

madrab

yeah you might have the wrong size c spanner

it was the same with my bros, but the way around this is to still put the c-spanner in the ridge & the rotate the wheel clockwise so that one of the bolts in the back of the wheel catches on the c-spanner. now when you start to rotate the wheel again it will move the c-spanner & tighten the chain

hope this works

Idleater

madrab wrote:

yeah you might have the wrong size c spanner

it was the same with my bros, but the way around this is to still put the c-spanner in the ridge & the rotate the wheel clockwise so that one of the bolts in the back of the wheel catches on the c-spanner. now when you start to rotate the wheel again it will move the c-spanner & tighten the chain

hope this works

Yeah, thats the trick all right. You place the spanner across two of the slots and then rotate the wheel against it either way to loosen or tighten. It really only has to move a couple of inches (at the tyre not at the nut).

Also, if you have a tight/lose spot on the chain, it might be best to put that on the ring rather than leaving it loose. IE tighten up the chain at its tightest rather than losest therefore minimising the risk of snapping the chain due to overtightening.

Once I was shown how to adjust the chain on the BROS it all became so easy....

L.

omb0wyn5ehpij9

nereid wrote:

Yeah, thats the trick all right. You place the spanner across two of the slots and then rotate the wheel against it either way to loosen or tighten. It really only has to move a couple of inches (at the tyre not at the nut).

Also, if you have a tight/lose spot on the chain, it might be best to put that on the ring rather than leaving it loose. IE tighten up the chain at its tightest rather than losest therefore minimising the risk of snapping the chain due to overtightening.

Once I was shown how to adjust the chain on the BROS it all became so easy....

L.

If you have a tight spot on your chain i would try get rid of it rather than tighten the chain at that point. If you have the time and patience Go around the links of the chain and move each one to make sure they are all moving. If they are aren't all moving, clean the links that are tight. I use wd40 and a rag and an old toothbrush. That should loosen it up a bit, then take it for a quick spin and lube the chain up when the chain is warm. Don't leave wd40 on your chain by the way

madrab

wd40 & a motorbike chain are 2 things that shouldnt go together, use proper chain lube if you are gonna do anything like that

Idleater

BrynW wrote:

If you have a tight spot on your chain i would try get rid of it rather than tighten the chain at that point.

Sorry, I may have written that wrong, what I was referring to was a where a section of chain has stretched more than another section. I can happen towards the end of the life of the chain, but if the chain is too loose then it needs to be adjusted anyway.

imagine a chain like _ _ _ _ __ __ __ __ _ _ _ _ _ _ _ _

I would put the stretched part __ __ __ __ at the rear sprocket so I would be tightening the chain "evenly" at the measuring point.

I had this at the last time I was adjusting the chain. I didnt move the stretched bit and when I adjusted the chain, the wheel would turn but when the tight bit got onto the the sprocket at the back the chain was so taught at the measuring point that it proably would snap straight if It was under any power from the engine.

L.

omb0wyn5ehpij9

madrab wrote:

wd40 & a motorbike chain are 2 things that shouldnt go together, use proper chain lube if you are gonna do anything like that

Chain lube doesn't clean your chain. WD40 does no damage to your bike chain IF you clean it off after cleaning the chain. Then go about your usual lubing technique and your chain will be grand

omb0wyn5ehpij9

nereid wrote:

Sorry, I may have written that wrong, what I was referring to was a where a section of chain has stretched more than another section. I can happen towards the end of the life of the chain, but if the chain is too loose then it needs to be adjusted anyway.

imagine a chain like _ _ _ _ __ __ __ __ _ _ _ _ _ _ _ _

I would put the stretched part __ __ __ __ at the rear sprocket so I would be tightening the chain "evenly" at the measuring point.

I had this at the last time I was adjusting the chain. I didnt move the stretched bit and when I adjusted the chain, the wheel would turn but when the tight bit got onto the the sprocket at the back the chain was so taught at the measuring point that it proably would snap straight if It was under any power from the engine.

L.

Ah right, sorry i took you up wrong. I thought you meant if there was a few tight links in the chain

Excellent - Thanks for the tips, I'll give that a go soon.