45 tooth rear sprocket over stock 43

[Bones]

Yeah I screwed up and ordered a 45 over a 43. I got it last night and of course assumed KLR650.com screwed up, but they didn't

Do I call in and ask them to exchange it with me paying shipping both ways or will it be THAT bad with a 15T front? I do 90% highway riding, little 2up and I do not haul much either, just what will fit into a pelican 1500.

I'd like to start buttoning this pig up someday

[tim]

start a collection - I have a dozen sprockets hanging on a zip tie I will never use!

or just use it and find that little bit of extra torque needed to power the KLR up in 3rd

[safiri]

The two teeth are going to make about a 5% difference (2/43 = 0.047) in your RPM. So cruising at 5000 rpm would become 5250. I would put it on and go unless your bike is near redline with the other gearing. I doubt you notice much difference.

A race car driving buddy told me anything less than a 10% change (I think ...) was hard to feel. Seems right to me.

Edit: Yes I have it backwards because my dislexia kicked in when I read the post ... ... dangit!

43 to a 45 will be a 5% reduction in rpm ... I still hold that this probably isn't enough to notice unless you are trying to climb something very steep in first gear near the stall point of the motor. Once you are out of first gear, and until you are in the last gear, this change won't make much of any difference, unless you shift by speed and not rpm. Each speed range for a set rpm range will increase by 5% ... adjust your shift points accordingly.

And BTW, Shiner is good beer!

[Bones]

43-45 I will gain more top end and have less grunt.

Safari I think you have it backwards. I also drank 10+ Shiner Bocks last night.

[Hayden]

The 43 will have a lower rpm at a given speed.

Smaller in the front----bigger in the back gives you lower gearing. So the 45 is bigger which will give you a lower gearing and higher RPM out on the HWY. 3 teeth either way on the back = 1 tooth on the front.

So for Hwy speed, you want the front and back sprockets to be closer in size to eachother (lower rpm) at a given speed. If you want slow rock crawling speed, make the rear as big as possible and the front as small as possible.

Your not going to notice the 45 that much if you have a stock front sprocket. Remember 3 teeth on the back = 1 front. So you didnt even drop = to one tooth on the front.

Hayden

[tim]

i think you will detect a difference. will it matter to you? try it and find out.

i can tell a difference in one tooth in the back right away if i pay attention to it. one in the front is a huge difference.

after riding it a little bit, the difference becomes the norm, until you change again.

[katbeanz]

Bones, you divide the number of teeth on the rear by the number of teeth on the front to get your final drive ratio. On my xrl for example, stock is 15-45, 45 divided by 15 is 3.
I run 14-49, for 3.5 but I don't do much highway. I used to run 15-53 on my old xl600, it's almost the same ratio as 14-49, 3.5333333~.
Using a 15 tooth front you had a final drive ratio of 2.86 with the 43 and with the 45 it will be 3, probably hard to notice much.

[Bones]

well if I hadn't dropped a bolt into the motor while doing the valves I would have tested it this weekend. Hoping to get it all buttoned up tonight and ride this week.

[Bones]

I need to make a call to KLR650.com as they sent me a 106 link chain which is stock with 2 master links and a 45 tooth rear sprocket over a 43 and with the wheel all the way forward I can get it to connect, but there is not much slack and I know by the time I set it on the ground (on a jack now) it will be far too tight

[andy2322302]

Use your extra 14 or 13 tooth counter shaft sprocket for the time being. The smaller outside diameter will give you the extra needed slack in your chain and the shorter wheelbase of the wheel being foreword will quicken your steering for the tight woods. But the downside of the shorter wheelbase is its more likely to rear up in a wheelie when you unleash the power to it.

[Harvey Mushman]

Andy is very knowledgeble when it comes to KLR650's. I once saw him put the smackdown on an XT-225 and a DR250 in a drag race. Both in the same day! He had his feet on the highway pegs too.

It's all I can do to stay with him on my 620.


-Harvey