Topic: cb550-4 1976 front sprocket

[andymum]

Hi
Is it possable to fix the freefloating sprocket so it doesnt flat as it is the floating that is causing the chain to rub on my frame

thanks

[bollingball]

I have a 750 it floats as it should. where is it rubbing and what type of chain is it? Any pictures would really help. Maybe some 500-550 guys can help. I don't think the floating is your problem.

[Johnie]

Welcome...I see you are rather new to the forum. I hope it is not rubbing on the engine case which will happen if someone put a o-ring chain on there. If that is the case you better not run it, but let's not jump to conclusions until you let us know where it it rubbing. If you take off the cover over the front sprocket you could tell if the chain is rubbing on the case. Look for the grooves. There has been issues with the 550 where an o-ring chain will rub through the engine case which is a real bad deal. I hope it is indeed only rubbing on the frame or in some cases rubs on the kick stand when the OEM exhaust is removed. Let us know what you find out.

[andymum]

Hi forgot to say its in a hardtail frame not rubbing on casinf just frame and rear wheel but sure fixing front sprocket will fix this as little room to play with

[andymum]

rear wheel

[cameron]

hmmm.
I also dont think it is the floating.

can we see a pic from directly behind the chain, looking forward?

[andymum]

Hi all

Thanks for your replys,

I have just looked at sprocket casing and it is ok no damage, there is enought play in front sprocket to make it touch frame,
the chain is an o ring chain

any help for you to aid in remedy

cheers

[TwoTired]

Unless you did something different than stock with the front sprocket, an oring chain is now (or will eventually) gouge the engine case and counter shaft seal next to the chain.  If you insist on a 530 oring chain then you will need to offset the front sprocket outward at least 1/8" to regain the required clearance.

[andymum]

Hi thanks for that there in is the problem

the front sprocket slides over the shaft then a groved washer goes onto shaft to lock sprocket into place with two 10mm bolts
and front sprocket has rocking movement too it
not certain how to off set or convert into fixed sprocket

[TwoTired]

not certain how to off set or convert into fixed sprocket

You don't want to make it a fixed sprocket.
The splined shaft allows the sprocket to "float" a bit, so it can maintain "self" alignment with the chain and not wear the chain side plates so rapidly.

Take off the front sprocket and have a look.  You'll see the base of it is wider than the tooth width.  Bring the sprocket to a machinist and have him mill one side flat and make a spacer the same width as the thickness he removed. Then put the sprocket back on with the spacer on the inside and the milled flat part on the outside.  That will gain your clearance back to save the engine case.

Personally, I would rather ditch the oring chain and just use a standard type, which is narrower and doesn't have clearance issues.  'Cause now, every time you wear out a front sprocket, you'll be back to the machine shop for another modification round to make a special part for the bike.  Or worse, you or whoever you sell the bike to won't remember the mod, and the bike will become a leaking damage engine case headache.

[andymum]

Oh ok will start to look for a standard chain for her

thanks

[cameron]

maybe by using a slightly smaller chain, you will even gain the clearance to make up for the rear end modification?

[Danno]

you can also buy a sprocket with a flat side to put out facing you when you put it on but you will still need the spacer to keep it out enough for that chain or if you insist on an oring chain get a smaller chain conversion

[LesterPiglet]

Did you get this problem fixed?

[andymum]

Hi peeps put a std chain on her and she is sweet now does anyone know if i can upgrade the carbs with modern ones if so which  thanks peeps

[cameron]

heh. "Modern Carbs".