15 tooth -13 tooth front sprocket

I think 13/49 will be the same as 14/52 which i tried once and sucked, top speed was 80/90 you had to change gears constantly and it will throw you over the bars everytime you back the throttle off.

Final drive gearing is a bit of personal preference there is no hard and fast rule, it also depends on engine size, torque, weight, primary drive ratio, gear ratio’s and tyre size. However if you are doing alot of single track you would usually gear your bike lower as speeds are reduced and there is less load on clutches, engines etc. Where as if you are doing more open trails and say some ADV riding thrown in and you need some fuel economy you would use higher gearing to keep engine RPM lower and speed higher.
For example on my KTM450 when I use it for single track work my gearing is 14/52 which equates to 3.71 to 1. This means that the counter shaft sprocket turns 3.71 times to the rear wheel turning once.
When I do an Adv ride I use 14/45 which equates to 3.21 to 1. It doesn’t sound like much but it does make a huge difference.

Hope this Helps, :blink:

Lefty

No worries Bob sounds good! The only thing that i would suggest is to keep an eye on your chain guide/runner that protects your swingarm next to the counter sprocket. As the smaller the gear the more the guide wears. Just a tip. You don’t want any swing arm damage eh.

Lefty

Steel frame WR’s run 14/50 standard & alloy frame 13/50.

14/50 on your bike would be ideal or as you have a 49 that’ll do.

You’ll be riding around in the high gears & won’t need first with the 13 front.

Bob,,it is good to see you have ellected to place the smaller option sprocket on the output shaft of your motorbike, please consider the extra wear this may place on your chain along with the probably strain on the output shaft. yamaha are a nice motor cycle but It really would be disappointing if you compromised the performance by the incorrect selection of chain drive sprocket. I appreciate your radical riding style would require the bike to be performing at its optimun at all times. please go back through the post and this may help you reconsider your choice,,or maybe your choice is the right one.

Good luck with the outcome,

see you on the trails champ!!

Boony

just bolt the bloody thing on bob and try it will just make it more snappy and more gear changes and slow on the road would get you through the weekend but will shit you

i just feel that the forces created from a smaller diameter sphere against the forces that would be generated from a slightly,although not greatly larger diameter sphere would be greater due to the increase ratio requiered to produce the needed final drive of your motorcycle.. Thus when a smaller sprocket is used on the output shaft it could nearly make the motor work a touch more compared to a larger sprocket. The roll over angle of the drive chain as it circumfrences the smaller 13 tooth sprocket will definatly shorten the life of the drive chain compared to if the chain was rolling around a 14 tooth sprocket. tighter circle more wear.

Boony