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R model low end grunt?

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my R model doesn't seem to have as much bottom end grunt as i think it should. my friend has 2 S models and one might have a E model motor in it.... has the E model base gasket for sure but has a S model carb on it. the thing has tons of bottom end power. he also has a stock motor S model and it has pretty decent bottom end power as well.

my bike has stock internals, fcr accel pump mod with the linkages wired together, 3x3, full yosh rs-3, and is jetted per Eddie with the stock needle.

i don't know if maybe his S model with the E model base gasket has a different needle in it and thats where it's getting the power, or if maybe it has stock S model cams and that's where it gets better low end, or maybe it's that it's a E model engine with a S model carb.

either way i have a S model carb and full jet kit, and a set of S model cams if needed.

any advice how i could get more bottom end?

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Bottom end grunt is a little hard to identify and means different things to different people. I call it friendly tractable power vs nervous energy. I have a 2000 DRZ400E, I have used all the combinations of carbs, and cams and gaskets and it always has the nervous feel. Not to say it will not pull strong from low revs with heavy throttle, but it just does not like to plunk around. It feels like a high compression "cammy" motor with not much flywheel.

The most friendly DRZ400S I ever rode belongs to a friend. It has an aftermarket exhaust and a 440 kit, S carb, unknown cams (probably S cams) and unknown anything else different plus geared 15/41 It is just a different motorcycle. Feels more like a mild cam, low compression, heavy flywheel motor. I wish I could tell you why. Fact is only the exhaust and 440 kit are known differences.

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i doubt my buddy's has a BB kit on it. but who knows? he bought it used and we rejetted it per Eddie to a stock S. it has exhaust and a 3x3 as well but the damn thing is like a tractor. i have a Athena kit for my bike as well but i was going to wait to put it in till my stock motor bites the dust. maybe i should put it on now?

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Try swapping exhausts and see what happens. I would be interested to know.

Also pull the top motor cover and verify what cams are in the S bike and if the cam timing marks line up. E cams are marked A and B. S cams are marked D and E.

Your motor may not "bite the dust" for many years.

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i didn't know that the cams were marked differently. i see if my buddy is curious enough to want to pull the valve cover.

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R model is the Kawasaki clone of the DRZ400E.

Your buddy wants to check the valve clearances anyway, right?

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My greenE likes revs also - doesn't seem comfortable much under 3000 out on the trails (may just be me trying to make sure there's no piston slap). However, geared 14/47-48 it tractors up anything I'm willing to try. I reckon it pulls well from low revs but the S models do seem to work well down low. I figure the E cams need more revs to develop more hp/torque.

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I have heard that the s cams only make slightly less power but really shift the power down low.... don't know how true that is.

Is there any way to tell if my buddies bike has a big bore installed other than removing the head? I know my athena kit is easy to spot but nit sure about other brands.

Oh yeah and I put s model gears on my bike.

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This is an interesting topic. My S model has E base gasket, E cams, MRD/SSW, fcr39 and im currently running 14/48 gearing on my SM rims. A nearly stock SM feels faster. Now i will say i couldnt rev to the limited with the stock cams/carb. With the fcr and E cams im constantly bouncing off the rev limiter. I feel like i have way more low end grunt than before but it goes through the revs faster. I think(just a guess) that the fact that it revs out quicker makes the stock(or close to stock) bike seem faster up top. I rode my bike and an SM back to back on sunday. I wish i could put my finger on it.

I will say this, the stock SM didnt feel like nearly as much bottom end. We are only 1 tooth off in the rear in terms of gearing..

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This is an interesting topic. My S model has E base gasket, E cams, MRD/SSW, fcr39 and im currently running 14/48 gearing on my SM rims. A nearly stock SM feels faster. Now i will say i couldnt rev to the limited with the stock cams/carb. With the fcr and E cams im constantly bouncing off the rev limiter. I feel like i have way more low end grunt than before but it goes through the revs faster. I think(just a guess) that the fact that it revs out quicker makes the stock(or close to stock) bike seem faster up top. I rode my bike and an SM back to back on sunday. I wish i could put my finger on it.

I will say this, the stock SM didnt feel like nearly as much bottom end. We are only 1 tooth off in the rear in terms of gearing..

I don't wonder that your SM has a ton of bottom end - that sucker's geared as low as my greenE when I take it into the mountains. I sure don't claim to know what a SM needs but it would seem you could at least put a 15 on the front and still have a ton of bottom end plus a better top end. Isn't stock gearing on those things something like 15/41?

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