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Revving, Lugging question

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So I'm 140 miles into my new 09 sm, loving it so far. Everything is running great, did the MCCT tensioner with no problems, changed oil smoothly recently. I have one question though. I've found that when I'm in areas where the speed limit is 35mph, it feels like im riding right between gears. Its either revving it up, which frankly isn't a lot of fun to ride around super-jerky, or lugging it in higher gear. I'm guessing its better for the engine to rev? I don't want to wear and tear my new baby more whats necessary...:thumbsup:

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the bike is surging. the drz carb comes tuned lean from the factory lean and a simple re jet will smooth the delivery out and help out with that damn surge your having

these engines liked to be wrung out, id rather keep the rpms high then lug it

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What gear are you running at 35? Stock gearing you are probably trying to be in 5th, but just a little too slow for 5th. Try 3 or 4th. Don't be afraid to rev it. And yes some jetting can smooth out the power delivery.

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What gear are you running at 35? Stock gearing you are probably trying to be in 5th, but just a little too slow for 5th. Try 3 or 4th. Don't be afraid to rev it. And yes some jetting can smooth out the power delivery.

5th? No no, I'm in second. I should state that when its 35mph, I'm trying to do about 40 or so...you know, keep it 'legal'. But still, its RIGHT between second and third. It's just so annoying to keep it in second and ride smoothly. I'm used to 2 strokes though, and I have no tach on the drz, but to me what I thought was right was second and revving..I shouldn't give it a 1/4 inch of throttle and lug it in 3rd to maintain 40mph, I assume this stressed the engine more. I wanted to make sure because I've found that new bikes inflict me with a certain amount of paranoia...which naturally happens I suppose when you have previously owned a lemon that requires a 5:1 fixing/riding time ratio...

Edited by ThanatosF
enlightening

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I'll preface this by saying I'm a light little bugger, like 145 with backpack filled with donuts. I tend to be able to run a little lower RPM without lugging the motor because I'm questionable skinny (100-200 revs lower) and found the same problem as you. I went to a 39 tooth rear sprocket and magic happened. I kid you not. There used to be a gear for not a single speed limit sign, and now there's a gear for every sign. The bike loves 65mph now, as well as 35mph and other oddball speeds there didn't used to be a gear for.

I just have 3x3, stock BSR carb and Yoshi's old RS-2 stainless F/S, which looks cooler than the new one. CV-K 40mm in the mail, though.. :thumbsup:

I set a new personal record today, set the front tire down at 67 mph. So it's not like the torque loss is unbearable.

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5th? No no, I'm in second. I should state that when its 35mph, I'm trying to do about 40 or so...you know, keep it 'legal'. But still, its RIGHT between second and third. It's just so annoying to keep it in second and ride smoothly. I'm used to 2 strokes though, and I have no tach on the drz, but to me what I thought was right was second and revving..I shouldn't give it a 1/4 inch of throttle and lug it in 3rd to maintain 40mph, I assume this stressed the engine more. I wanted to make sure because I've found that new bikes inflict me with a certain amount of paranoia...which naturally happens I suppose when you have previously owned a lemon that requires a 5:1 fixing/riding time ratio...

your not lugging it if do'in 35mph in 2nd...when my sm was stock 4th gear would have been comfy to cruise at 38mph...(60kmh)

if your chain is got too much freeplay it can chug a bit if not in a low gear...

Try a JD jet kit to see if it smooths things out for you...you may be getting some lean surge...

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I forgot to mention that I jetted it properly (with the BSR carb) before the sprocket, and that fixed a whole bunch of things too. Simply cruising in the mid RPM range on a stock sm yields much popping and surging.

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I find that with my stock SM gearing, My revs are about 150 RPM lower than my speed. 40 MPH, would be about 3850 RPM. 60 MPH is about 5850 RPM.

When just cruising, I don't like anything lower than 3500 RPM. If I'm accelerating, or going up a hill, then I keep the revs above 4K.

Maybe you aren't used to a single cylinder?

Steve

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