Perhaps a sprocket change for lower revs?

[meowguy_imp]

I was having a discussion with a member of another forum who is driving a Honda 919. His has a six speed, but he found the revs annoyingly high at highway speeds. His solution was to put a sprocket on the counter shaft with one tooth more (from 16 to 17 teeth). This did not require a new chain.

Anyone have any thoughts on this? I feel the bike has plenty of power to deal with this at the low end.

 

[the Ferret]

Common modification to the 750 Nighthawk which also has a 5 speed trans. One tooth usually equals about a 400 rpm difference. I bought one for my 750 Nighthawk but never put it on. It's sitting in the garage someplace.

 

[cbfan_imp]

I had a 650 Vstrom and went from 14 to 16 sprocket sure made it nice at cruising speeds (lower RPM less buzz) and still had good torque..............not to mention better MPG's.

 

[the Ferret]

One has to be careful when making changes to the gearing for chain clearance inside the sprocket cover. On the Nighthawk 750 one tooth on the counter was good, but 2 teeth on the counter wouldn't fit. Guys then would go with 1 up on the counter and 3 down on the rear.

 

[rboe]

Are aftermarket sprockets available in different sized yet?

 

[the Ferret]

SuperSprox

 

[rboe]

Thanks! :worship: Looks like their choices have expanded (this is a good thing). But $370 for a rear sprocket is a nose bleeder.

 

[the Ferret]

Lol everything for this bike is nutty $

 

[flynrider]

JT and Sunstar are usually good sources, but it looks like they haven't got much for the CB1100 yet. Sunstar doesn't have anything and JT only sells the stock 18/39 sizes. I suspect they haven't really seen much of a market have a feeling they'll have more options as time goes on. The market for CB1100 sprockets is probably near non-existent today.

 

[CA200_imp]

I was just over at JT's site and they do list a update but it looks like they will only some to lower the gearing
JT Sprockets: Catalogue

 

[the Ferret]

It looks like the front sprocket fits a lot of Hondas if I read the chart right by searching by part number JTF 339. Perhaps someone makes a 1 tooth larger sprocket for one of those models. I notice it did say that sprocket was for a # 50 chain, where ours takes a # 530 chain, but what I'm not sure of is the difference between those two.

 

[Randy B]

Ferret that's most likely a typo. The Nighthawk 750 uses a #520 chain and the CB1100 uses a #530 chain for reference.

 

[meowguy_imp]

Thanks for all the input on this topic. I guess I am not the least bit interested in blazing a new trail on this so I'm going to wait until someone else actually does it first. I am just too old and I have no hair left to pull out.

 

[IndianRider_imp]

I'd be interested in going one tooth larger on the front sprocket once it's available .. The JT sprocket website only lists the stock front 18 tooth .. 19 tooth front sprocket is not available yet .. You can also go smaller than stock in the rear sprocket but it's not available either and it's more work and $$ switching out the rear ..

I have done this simple cheap mod on a couple of my previous bikes .. The revs are lower on top gear and feels relaxed on the freeway without a noticeable loss in torque/power .. I also felt that the engine breaking is softer and taller gearing allows for holding the gear longer in the 2,3,4 th gear twistes .. The mpg generally get slightly better too in my personal experience

 

[Tyke57nz_imp]

I'd be interested in going one tooth larger on the front sprocket once it's available .. The JT sprocket website only lists the stock front 18 tooth .. 19 tooth front sprocket is not available yet .. You can also go smaller than stock in the rear sprocket but it's not available either and it's more work and $$ switching out the rear ..

I have done this simple cheap mod on a couple of my previous bikes .. The revs are lower on top gear and feels relaxed on the freeway without a noticeable loss in torque/power .. I also felt that the engine breaking is softer and taller gearing allows for holding the gear longer in the 2,3,4 th gear twistes .. The mpg generally get slightly better too in my personal experience

I would be up for a change to a larger front sprocket when and if they become available.

 

[736cc_imp]

Sprocket Specialists can make any size rear sprocket for any motorcycle. Just mail your stock sprocket and by using that bolt pattern on one of their blanks, any # of teeth can be had. They can also "Swiss cheese" it w/ lotsa trick holes! Very reasonably priced, too .
That may be only possible for rear sprockets as front sprockets sometimes need special machining.

 

[jeffskar_imp]

Has anyone increased the rear sprocket size or decreased the front sprocket size for a better take-off at the drag-strip? I'd like to go as extreme as possible and also use the same chain while doing so, and also have no interference.

 

[Lord Popgun]

Some have changed the front sprocket at least. Here is one thread on it: 19 tooth countershaft sprocket installation on 2013