Increase top end with new sprockets

[jrdport]

I have a 4 speed sportster that revs high on the highway. Any recommendations on how to increase top end?

[Dragstews]

Aaaaaa...Stroke it....

Tall gearing needs to have the power to pull...

The counter shaft gear would be the easy way to get more..
Don't go to high with the tooth count, will cause the chain to get into the sprocket cover and perhaps the dowel pin on the case..
================================================== ====

First post here I see.... May want to say Howdy in the intro....
Helps on keeping the Peace....

[Creepinogie]

Just add a sprocket with one more tooth to your countershaft. It'll drop your rpms.
You should have plenty of power. Depending on the year your bike was made it may have been geared for the lower speed limits back then. I've done it on pretty much every sportster and shovelhead I've had. Even my chief.

[Wagoneer]

They make 23 and 24 tooth sprockets for the transmission sprocket.

However.....I have a 22 tooth on my Ironhead and I had to clearance the sprocket cover with a 520 chain.

The 22 is fine, to me.

Some of the earlier bikes had sprockets as few as 18 or 19 teeth I think. Yowzers!

How many teeth you got on there now???

[jrdport]

I had a 21 tooth on the front and opted to buy a 23 tooth. I'll let you know how it works out. Thank for the tip

[fingers]

Any change is good

[shovithead]

23 should get you there. And just in case, make sure you run a non o ring chain on there. The o ring chains are to wide and eat into the motor/trans case.

[rooster52478]

I run a 22/49 on my '80 with the disc brake. Stock is 21/51 I think?

[Hoofhearted]

Go up one on the trans if there's room or drop 3 on the wheel. Anything more might be too much of a change.

[shovithead]

Originally Posted by Hoofhearted

Go up one on the trans if there's room or drop 3 on the wheel. Anything more might be too much of a change.

If it is a drum rear, his only option is the front sprocket.

[kickstarts]

What year is it? 4 speed could mean anywhere from 57-90.

[16ouncePBR]

Originally Posted by shovithead

If it is a drum rear, his only option is the front sprocket.

I think PBI makes down to a 49 for the XL drums, but have heard of chain clearance issues on the drum as it drops the chain closer to the outside of the drum.

[FeHd]

Put a rear disc on it, thats what I did, I run a 48/21. And have a real rear brake too.

[shovithead]

Originally Posted by 16ouncePBR

I think PBI makes down to a 49 for the XL drums, but have heard of chain clearance issues on the drum as it drops the chain closer to the outside of the drum.

Good luck with that one. Yeah, they make em, but they are junk and eat the drum up, and with little wear, they eat the drum.

As far as going to a disc, they don't stop the bike any faster than a drum, and much more expensive, to get down another tooth or two. Sportsters ran drums on the rear, from the beginning, and front sprockets have always been the cure. If you are trying to get the "perfect" setup, you may have to spend a lot more money and get something that has a disc and sprocket, seperately.

I am willing to bet that the 23 will get him where he needs to be, unless he is drag racing.

[FeHd]

I'm gonna have to disagree with the statement that discs dont stop the bike any faster then drums. Of course on the rear both will lock up the wheel, but on the front the Brembo caliper I have on my 74 stops WAY better then any front drum.

[kickstarts]

Originally Posted by FeHd

I'm gonna have to disagree with the statement that discs dont stop the bike any faster then drums. Of course on the rear both will lock up the wheel, but on the front the Brembo caliper I have on my 74 stops WAY better then any front drum.

I think he was talking about the rear brake.

I'll have to agree with both of you. The drum on the back of a Sportster, if set up correctly, I've found to be vastly superior to a factory rear disc brake. As far as a front brake goes, a disc wins hands down in my opinion.

[Dan Boy]

You want to make changes real slow with sprockets as you will be surprised how much difference 1 tooth will make.

Either go 1 tooth up on the front or 1 tooth down on the rear and feel the difference. When I used to race I had an array of front and rear sprockets that I would tailor for whatever track we were racing at.

Cheers Dan.

[FeHd]

Originally Posted by kickstarts

I think he was talking about the rear brake.

I'll have to agree with both of you. The drum on the back of a Sportster, if set up correctly, I've found to be vastly superior to a factory rear disc brake. As far as a front brake goes, a disc wins hands down in my opinion.

Oh yea for sure. Thats why my rear disc is a Nissin 2 piston from a rice rocket mounted to be full floating. Call me crazy, But I LIKE good brakes.