What hasn't been mentioned and should be is which rear wheel you're running, a 16 or an 18. The wheel size equates to about 1 tooth on the rear sprocket. A 16 with a 32 will turn about the same RPMs as an 18 with a 33.
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18T Counter Sprocket Ok?
- Thread starter rwingsfan
- Start date
Classic
rackin' up the miles
I'm going to get an 18/30 combo with a 520 chain. Should I get a 102 link or 104?
EDIT: Never mind, going to go with 17/30 530 with 100 links.
EDIT: Never mind, going to go with 17/30 530 with 100 links.
Last edited:
Newagerocker
XS650 Addict
Have you considered 17/32T, 102 L, probably the most common conversion. Offers a 6% RPM reduction and can more easily reach the max torque point in higher gears.
Classic
rackin' up the miles
I need to be able to cruise at 85mph minimum. I make max torque right off idle with my setup.
AussieHard
AussieHardTail
The more I read the more I get confussed!
I have to get a rear sprocket made up as I am fitting a 18" Harley rear rim with either a 180/200.
I am running an offset sprocket on the front so that is a fixed 18T
The bike is a rigid.
What would the best general purpose ratio be?
As for chains I thought the link count would be decided by the distance between sprockets and also be a fixed number.
I have to get a rear sprocket made up as I am fitting a 18" Harley rear rim with either a 180/200.
I am running an offset sprocket on the front so that is a fixed 18T
The bike is a rigid.
What would the best general purpose ratio be?
As for chains I thought the link count would be decided by the distance between sprockets and also be a fixed number.
BigJimmyW13
XS650 Guru
Pete's Spreadsheet regarding ratios
As for chains I thought the link count would be decided by the distance between sprockets and also be a fixed number.
It is. Depending on sprocket sizes and the distance between sprockets.
Classic, if you need to cruise at 85 mph + then maybe you need a bigger bike. With the 17/30 cruising at 80-85 isn't hard to do.
As I said before the 17/30 works ok at highway speeds. The 17/34 is ok around town. The 17/32 is a good compromise. Not so high as to work the clutch to hard, yet high enough so high way vibes are ok.
If I was running a lightweight bike, a chopper or bobber then using the 18 up front might be ok as long as you don't crry a load. Like traveling. On the stock like bikes loaded for travel with a passenger I think the 17/32 will be better.
On moddified engines as in Mike's 750 kit or a rephase can greatly reduce higher rpm vibes. This can make long trips easier with out reducing the rear sprocket so much.
My 75 with the Mike's 750 kit, even with the extra power works the clutch noticeably harder with the taller gears. Especially when loaded with a few weeks worth of camping gear.
All these reasons are why I think the 17/32 is a good all around combo.
As I said before the 17/30 works ok at highway speeds. The 17/34 is ok around town. The 17/32 is a good compromise. Not so high as to work the clutch to hard, yet high enough so high way vibes are ok.
If I was running a lightweight bike, a chopper or bobber then using the 18 up front might be ok as long as you don't crry a load. Like traveling. On the stock like bikes loaded for travel with a passenger I think the 17/32 will be better.
On moddified engines as in Mike's 750 kit or a rephase can greatly reduce higher rpm vibes. This can make long trips easier with out reducing the rear sprocket so much.
My 75 with the Mike's 750 kit, even with the extra power works the clutch noticeably harder with the taller gears. Especially when loaded with a few weeks worth of camping gear.
All these reasons are why I think the 17/32 is a good all around combo.
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Newagerocker
XS650 Addict
What's your setup consist of?
BigJimmyW13
XS650 Guru
Unless he didn't do what he said he was going to earlier in the thread. 17/30
I just thought of the reason people use an 18 on the front. An 18 front sprocket is cheaper than a 32 rear sprocket. And easier to change.
Classic
rackin' up the miles
It also brings the chain up a little bit so you can run near 14in shocks without dragging on the swingarm pivot.
My setup is nothing special. Just retarded timing, weak atu springs, uni pods, jbm manifolds, and vance and hines cruzer pipes.
My setup is nothing special. Just retarded timing, weak atu springs, uni pods, jbm manifolds, and vance and hines cruzer pipes.
Newagerocker
XS650 Addict
I'm curious as to why you say that? Your setup wouldn't seem to alter the characteristics of the engine that much. Have you had it dyno'ed? These engines typically reach max torque at 6,000 rpm. I understand what you say about the 18T raising the chain off the swing arm. If you go too extreme you'll give up too much at the bottom to make the ride enjoyable. 6,000 rpm on a stock sprocketed bike is just below your targeted 85 mph at 83 mph. Seems an 18T,34Tcombo would get you what you want with the least investment - one counter shaft sprocket and some filing.
Classic
rackin' up the miles
I'd like to get it dyno'd but I'm not sure i'll get around to it.
Mikexs has dynosheets on his site that show that torque peaks at 3500rpm, drops, then continues to rise up to that same torque number at redline. With my timing i back off that early torque peak about 900rpm. I don't make any torque on the high end. Wouldn't want to anyway. I have a feeling the sharp angled head pipes might also contribute to the change in power delivery. I've ridden a few other xs's and this one is the most responsive at low rpm.
Wow this thread is waaay off topic. I'll have to dyno this thing for you guys.
Mikexs has dynosheets on his site that show that torque peaks at 3500rpm, drops, then continues to rise up to that same torque number at redline. With my timing i back off that early torque peak about 900rpm. I don't make any torque on the high end. Wouldn't want to anyway. I have a feeling the sharp angled head pipes might also contribute to the change in power delivery. I've ridden a few other xs's and this one is the most responsive at low rpm.
Wow this thread is waaay off topic. I'll have to dyno this thing for you guys.
alfredo
1978 xs650 Special
going with a 17/32 530 setup. . . . stock swingarm. Anyone help a brotha' out on how many links I need to order?
Newagerocker
XS650 Addict
102L. You've reduced rear by two teeth you subtract two teeth from stock 104L.
My swingarm bike came with a 17/34 and a 530 chain. I recently switched to an 18/34 and 520 chain. It is tight but I stay on top of chain adjustments. I've noticed little difference and will consider another tooth smaller on the rear.
I was wondering if anyone ever thought about designing a spring loaded or hydraulic idler for the swingarm bikes?
I was wondering if anyone ever thought about designing a spring loaded or hydraulic idler for the swingarm bikes?
Adding a tooth on the front is the same as subtracting two from the rear.
