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15/49 vs 14/50 gearing performance


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Hey can anyone tell me how much of a performance decrease I will experience with a change from stock 14/50 to 15/49 gearing??? I have done some rejetting right when I changed out my sprockets and chain and my bike is definitely slower feeling, the front wheel seems more or less glued to the ground now. I don´t know whether to blame the gearing or the Jetting changes. How fast should this thing be with this gearing? This is a 99 400, basicaly stock with the normal free mods and a pmb insert. Should I be seeing roll on wheelies easily with this gearing? Cuz I AINT. ? I threw away my old spockets, they were trashed.

Thanks,

Mark...

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Adding one tooth to the front is like dropping three from the back. The bike will be faster overall but not as quick.

I hit 89.8 mph on my 01 WR 426 with stock 14/50 gearing running across Soggy Dry Lake. Then I started hitting the rev limiter. My buddy on his 99? WR 400 with 14/47 hit 90 he had me by a hair in top speed. I think he hit at least 91 mph. I pulled him at first but then his top end gearing out lasted me at the very very top.

I have better real world bottom end pull. Both bikes run great.

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Gee one whole tooth on the back would make a 2/10ths of bugger all, be surprised if you would even be able to feel it!!!

You forgot the change to 15 on the front.

I believe changing the front sprocket larger slows the motor response down too much.

I would keep the 14 on the front and drop to a 48 on the rear. You will still have heaps of pick up, just more speed up top.

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I've tried 14 / 44 with good results for open spaces and light trails. Still have lots of acceleration and spinning. Tried 15 / 44 and it slows a bit. I think it is too long even for open spaces. I will keep the 14 / 44 with higher mileage and still fast.

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Hey can anyone tell me how much of a performance decrease I will experience with a change from stock 14/50 to 15/49 gearing??? I have done some rejetting right when I changed out my sprockets and chain and my bike is definitely slower feeling, the front wheel seems more or less glued to the ground now. I don´t know whether to blame the gearing or the Jetting changes. How fast should this thing be with this gearing? This is a 99 400, basicaly stock with the normal free mods and a pmb insert. Should I be seeing roll on wheelies easily with this gearing? Cuz I AINT. ? I threw away my old spockets, they were trashed.

Thanks,

Mark...

Well, do the math. A 14/50 combo is a 3:57 ratio, while the 15/49 is a 3:27. This will be pretty noticable. But just going one more tooth in the front is almost identical, and you wont have to spend the extra on a rea spocket. With an existing ratio of 14/50 (3:57) this means for each tooth you add in the front, its like adding 3.57 in the rear. Of course, you cant add 3 and a half teeth, so its bacially equal between 3 and 4 in the rear. When I replace my sprockets/chain, I'm keeping the 14 up front (less wear on the chain, slider etc) and bump up 2 in the rear to a 52 for a nice 3:71 and if I ever need to pull stumps, drop the front to a 13 for a 4.0:1

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Quoted material:

My question is what were you hoping to get out of this gearing change. Top end speed or a more torque frond end snap feel?

Well, I know it´s kind of an insult to the pedigree of this bike, but I use this thing mainly for transportation. I was just looking to get the revs down a bit on the autoban (ha... right). I think I´ll go back to a 14 in the front and keep the 49 on the rear, at least to get a grip on whether the performance decrease has anything at all to do with the new jetting or not.

mark...

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i doubt its even relevant but i'll say it anyway, without doing the maths most of the guys i know use the 1 tooth up front = 4 teeth out back. and taller gearing just spreads your power out, as previously stated by toyota_mdt_tech if you wanna pull stumps go a 13 front (ie drop teeth out front or add out back)

i recently went from the '04 yzf gearing (14:50) to the wr gearing (15:50) and i couldnt be happier, it broadened out the power i already had and witht he wr gearboxi can still almost climb trees in 1st and geez does 5th haul ass.

at the end of the day its horses for courses, the peak power wont change, just where its made. tight stuff, gear it down. open fast stuff gear it up . but you all already knew that didnt ya?

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I just geared my 02 down a tooth in the front. I run a lot of tight woods and large sandy whoops (poor trail maintenance here in Michigan.) I clocked my top end with stock gearing at 86.9 mph on a dirt road last year. I lost 5.5mph dropping a tooth in the front, but now I can run 3rd/4th gear in the whoops and mostly 3rd gear in the woods (except for the really tight stuff)

Did I mention the fun of 3rd gear roll-on wheelies? Basically, just gear your bike to suit your riding style and it will be much more enjoyable and less taxing on your body when you ride it.

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