Topic: CB500 largest rear sprocket?

[Terry in Australia]

Quick question folks, I'm about to fit my Lesters on one of my CB750's. Trouble is, the rear is for a CB500, and the largest rear sprocket I can find for a CB500 is 37 teeth. I need a minimum of 44 teeth, and preferably a 48 T rear sprocket, does anyone know where I can get one? Cheers, Terry.

[PeWe]

Not possible to find a sprocket you drill the needed holes to fit it on the wheel, carrier?

[Terry in Australia]

Not possible to find a sprocket you drill the needed holes to fit it on the wheel, carrier?

Thanks Per, yep I can probably buy a plain sprocket from an engineering supplier, but in my experience they aren't as hard as motorcycle sprockets, and wear very quickly. I'm hoping someone who's raced CB500F's has knowledge of a supplier of bigger sprockets, maybe for drag racing/hill climbing etc?

[Nicklopic]

You can order custom sprockets, rears are easy to make and at least in the states there’s plenty of people who make them however you want.
Basically all you need is tooth count, chain type you want, center bore, bolt pattern and bolt hole diameter.
I ordered a sprocket from PBI for my bike. Idk how bad it would be getting it shipped to you but it’s a back up

[PeWe]

Not possible to find a sprocket you drill the needed holes to fit it on the wheel, carrier?

Thanks Per, yep I can probably buy a plain sprocket from an engineering supplier, but in my experience they aren't as hard as motorcycle sprockets, and wear very quickly. I'm hoping someone who's raced CB500F's has knowledge of a supplier of bigger sprockets, maybe for drag racing/hill climbing etc?

Not general sprockets for automation industry, motorcycle sprockets for real men !!

Like this.
http://www.rebelgears.com/ 

I have seen many others offering motorcycle sprockets to be drilled by yourself since many years.

Forum member bwaller might know.

[bryanj]

Terry, 37 was biggest from Honda. Dont know what 450 or 500 twin had as they were same hub. You can get a 16 front here in UK and with modern chains should be OK, Honda went up on front with 750 to help stop chain breakage

[madmtnmotors]

I get my custom sprockets here:

https://sprocketspecialists.com/product/rear-sprocket/

[Alan F.]

Just spotted this one Terry, Happy Birthday!

https://www.ebay.com/itm/73-Honda-CB500-CB-500-Rear-Drive-Sprocket-Gear-48T/401075331177?hash=item5d61f3e069:g:wD0AAOSwoMhfRQPH

[754]

Most makers will fix you up . Tge ebay one lokks likea 750 one.
 Why not just press in an adaptor, and re drill a 750 sprocket, wnt take an hour..
 I have mentioned before , you could really use a mill.. make your life easy..

[low-side]

The sprocket carrier that came with my Lester for a 550 accepts a CB750 sprocket.  I think that the wheel was on a later 550 because it came with a 630 sprocket, but my 48 tooth 530 sprocket matches bolt pattern and pilot bore.

[Alan F.]

Didn't 500/550 sprockets have a 94mm center bore while 750 had 80mm?

The same seller has another listed a 73 cb750, maybe they're the same, maybe not.

[Terry in Australia]

Thanks guys, much appreciated. I think the 550 has the same sprocket carrier as the 750, but not the 500 and they’re not interchangeable. I have a Mill/Drill with a rotary table Frank, so could easily modify a “plain” sprocket to suit, I just don’t want a soft industrial sprocket that’s gonna wear out quickly.

I do have a minty 15 tooth front sprocket (off a K0, from memory) that I might try as an interim measure until I can get a larger rear sprocket. I’ll just need to remember to keep my wheelies and burnouts to a minimum.....

[754]

15 is a chain killer on our bikes.

[Terry in Australia]

Bugger. OK, I'll have a re-think.

[754]

Better to wear out a few cheap rear sprockets , than to punch a hole in your cases..

[dave500]

the first 550 had same as 500 rear hub but 37 teeth,the lester might use the later style hub?you checked JT sprockets catalouge?

[Terry in Australia]

Thanks Dave, I’ll check it out.

[bryanj]

All the 500 and 550 used the same sprocket and brake shoes it was only the brake plate and associated hub machining which changed plus the rubber cushes were modified

[dave500]

JT list the 500 and 550 rear as JT282,only comes in 34,36,37.

[Terry in Australia]

Yeah, I pulled the 15T sprocket out of the tub it's been sitting in for years and compared it to an 18 toother, and it doesn't look that small? Hmmnnn.......

18T vs 15T sprocket by Terry Prendergast, on Flickr

[bryanj]

3 on the front would be 6 on the rear

[Terry in Australia]

Thanks Bryan, that’s what I’m thinking too. The gearing would still be a little high, but not horrible. I think I’ve got a K0 case guard somewhere, I might have to go looking for it.

[754]

 If   i were odering one , it would be Aluminum.. 7075 is pretty tough, never had rapid wear on an Aluminum rear.
 AT The Sprocket makers .. some get drilled for  specific popular  models.... and they keep   some blanks in stock for cudom orders..  then machine to fit ... Alloy is light to ship.

 If they are hobbed they cut a whole stack of blanks to a specific tooth size in one setup..

[Terry in Australia]

I get my custom sprockets here:

https://sprocketspecialists.com/product/rear-sprocket/

Thanks mate, I just ordered a 48 tooth rear, $125.99 USD with shipping, but as Frank rightly says, sprockets are cheaper than cases. Of course I might still use my little front sprocket along with the 37 tooth rear I bought for the lester rear wheel until the new one arrives, but as you all know, "Safety" is my middle name, so I promise I'll be careful until then.........

[Bodi]

I though "Give'er" was your middle name...