Front chain drive sprocket

[steve452]

If all goes well I shall shortly be re-installing the front sprocket. The manual advises torqueing the retaining nut to 12-15kg/m. I managed to remove it with my air impact wrench but cannot remember how I locked it to install it in the first place. The wrench does not have torque settings although it does have 4 separate force settings which are not detailed in the manual. What's the best way to lock the sprocket to tighten the nut up?

[MrDavo]

There's a KHI tool that goes in holes drilled in the sprocket to hold it while you tighten the nut.

I was offered use of one of these tools on here, but my sprocket has no holes. Instead I put a clean folded up cloth between chain and sprocket to jam it while I tightened the nut. I've done many primary and final drives this way, and hardly ever had a problem. the one time I did, my HD's crank sprocket nut flew off and wrecked the casing but that was because it wasn't tight enough (150 ft lbs I think!). I borrowed a large torque wrench and redid it, using a rag, it's not come loose again.

[steve452]

The thing that worries me with that is that if the sprocket spins round whilst the nut's being tightened there's a risk the chain will hit the molding on the transmission cover and break it off. That's what happened to my original!

[Mr Bump]

You can wait till the bike is fairly complete, stick it in gear, stand on the back brake and torque it up while sitting on the bike.

Another way, if there's room, is to use a clutch holding tool (the type that looks like a pair of mole grips with a long extension on the end) to hold the sprocket.

Olly

[steve452]

Hi Olly,

Thanks for that. Unfortunately I re-installed the RHS covers first so the clutch has been rebuilt and the cover gasketed back on!

Your back brake idea sounds good. I think I'll go along that route. There's no particular rush considering the bike has been in pieces for 43 years

[steve452]

Well, Olly's back brake tip worked perfectly and the front sprocket nut is now tightened to around 100 ft/lb. Unfortunately I had fun and games with the split link as can be seen from the photo. I didn't realise that you still had to compress the side plate onto the link with the chain rivet tool and so had the same problem as previously when I tried to fit a soft rivet link. Following that disaster I went for the spring-clip split-link type thinking it would be easier. Well there's no fool like an old complete nobhead! I still had to apply so much compression to get the linkplate over the pins that I nearly pulled a muscle again (which I actually did in the first attempt last year). I did actually manage to get it to the point where it had compressed past the grooves on the pins for the spring-clip to seat. Nobhead skill Mk II then took effect as I managed to clip it on in the wrong direction! My attempts to get it off and back on again resulted in the clip bending and now refusing to seat properly as per the pic.

I have finally decided that my Oxford chain riveter is crap (although to give it it's due it does clearly say on the box it's for up to a 530 chain and I have a 630 XW-Ring). Can anyone recommend a top quality chain-rivet tool that does not need the muscles of an olympic weightlifter to use? Cost is not an issue as long as it's good value for money. I am wont to go back down the soft rivet route again if I can get the right tool for the job.

TIA guys.

[Gavin]

I usually put a split link in then ride it up to my local bike repair shop and ask them to fit the rivet link for me approx £5 then take the split link home again for next time

[steve452]

Am going to make another attempt to fit a rivet link using the new soopa-doopa german tool I've just bought from Ralph. Fingers crossed,

[Adrianbrooksbank]

The best tool for all chain sizes is the WHALE type riveting tool approx £90 and do a perfect job. The tool has pin to disconnect chain and able to put side plates on and rivet properly using a hammer and they last well and made well had mine 20 years and used it at local bike shop to do customers. Hope this helps

[steve452]

... using a hammer ... at local bike shop to do customers.

Only for the ones who argued about the cost, surely