PDA

View Full Version : changing rear sprocket?


rickieh
04-22-2013, 01:33 PM
what must be done to make the rear sprocket a little smaller for increased top speed and better cruising?do you have to take the back brake and wheel off and realign everything?

FastDoc
04-22-2013, 01:39 PM
Pretty simple. Remove wheel.

Sprocket comes off with a circlip. Needle nose pliers may work but snap ring pliers make the job easier.

Transfer the locating dowels from the old to the new sprocket and reinstall.

The only 'issue' is you may need to shorten the chain. This involves a chain breaking tool (cheap at HF, but I don't know if it works on 428 chain), or a grinder and a punch and hammer. I do the latter.

rickieh
04-22-2013, 01:50 PM
yeah ive shortened a chain before but i wont have to do any alignment?

FastDoc
04-22-2013, 02:02 PM
No worries.

SpudRider
04-22-2013, 11:00 PM
yeah ive shortened a chain before but i wont have to do any alignment?
Changing sprockets, shortening a chain, and installing a new drive chain are foolproof procedures. As long as you don't make the drive chain too short, you really can't mess things up. ;)

Spud :)

FastDoc
04-23-2013, 12:55 PM
Or unless the snap ring flys off the pliers into God knows where in the garage....

2twisty
04-23-2013, 04:01 PM
Or the snap ring slowly wears out the groove in the hub and breaks the groove in the hub off, dropping your sprocket onto the axle bolt. 8O :x

I solved this by tapping the holes in the bushing inserts in the hub and epoxying studs into them. I then slid the sprocket over my new studs and attached lock washers and nuts. Then, I cut the studs to the appropriate length.

I figure that many, many bikes don't have that floating design, so what the hell... I have at least 500 miles on it since then with no sign of any increased wear (although it is time for a new rear sprocket due to general wear)

FastDoc
04-23-2013, 04:04 PM
I think if a 60+ HP KTM can get by without a cush drive a 15 HP or so 200cc trailbike won't hammer anything too bad. :wink:

SpudRider
04-23-2013, 05:00 PM
I think if a 60+ HP KTM can get by without a cush drive a 15 HP or so 200cc trailbike won't hammer anything too bad. :wink:
I agree completely. ;) These 200cc, air cooled engines don't require any kind of cush drive on the rear wheel.

Spud :)

Trailbikeryder
04-23-2013, 05:08 PM
How can I tell what size my chain is?

FastDoc
04-23-2013, 05:13 PM
Almost every CB I've seen is a 428

SpudRider
04-23-2013, 08:37 PM
How can I tell what size my chain is?
Measure the pitch, and the chart at the following link will tell you the chain size. ;)

http://www.gizmology.net/sprockets.htm

I would be very surprised if your chain is not size 428. ;)

Spud :)

Trailbikeryder
04-24-2013, 05:40 AM
THanks. Now I know which chain to order at my parts dealer for
my "project bike" 8) when I need one.

SpudRider
04-24-2013, 12:00 PM
You're welcome. :)

Spud :)