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40k mile 98 r1 on the dyno


porter_jamie

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dropped it off friday night, so he can have a look at the the needles. motor is bog stock apart from lowered gearing, and a coil spring clutch (which won't make a difference) and a can off a 99/2000 model.

what do you reckon it will pull? 120odd? if i'm lucky?

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So much depends on dyno/conditions of course, but mine put out 127 at about 20,000 miles and it was a bog stock 2/3 year old at that point. They reckoned that was a good 'un.

I bet 120.

Mitch

Edit to add, it was 137 actually, not 127. It had done a few track days to loosen it up. So I reckon yours will be nearer 130 than 120.

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Hopefully popping mine down next weekend for a power run to check if its still fit.

What do we reckon?

45t sprocket, dyno jet, K&N, end can, 9k miles?

:eusa_whistle:

Hope it doesn`t shit itself....

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Not sure what relevance the gearing has to the dyno figures - Shirley it will make the same bhp/torque regardless of the gearing?

my 4xv made 131bhp at Gibson's dyno recently - that's with a full akra system, re-jet and a K&N, it had about 35,000 on the clock at the time.

Haven't tested the new engine yet though

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Not sure what relevance the gearing has to the dyno figures - Shirley it will make the same bhp/torque regardless of the gearing?

my 4xv made 131bhp at Gibson's dyno recently - that's with a full akra system, re-jet and a K&N, it had about 35,000 on the clock at the time.

Haven't tested the new engine yet though

it shouldnt make any difference, unless it can tell the difference between a steel rear sprocket and an ally one!

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er, inertia dynos dont measure torque. well ok, the 250i ones do, but you know what mean. they measure rate of change of rpm a known mass, and infer the torque from there.

it knows the engine rpm, the drum rpm and works it all out from there. i think.

so if you use a carbon rear wheel you should get more power than a mag one, because the mass you are accelerating is less

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For what it is worth:

Standard 99 R1 20k miles West London Suzuki dyno day 133 ish

lightly modded(ivan's needles, 120 mains, full akra, piperx filter) 99 R1 13k miles Steve Jordan Suzuki 138 bhp last time up

So depending on the dyno and prevailing winds 125-135 bhp for your one!

Unless you use the same dyno for before and after mods comparison, it can be pretty meaningless.

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The measured/calculated power has increased (although i seriously doubt you'd ever be able to measure the "power" increase going from a mag to carbon wheel) and in reality the power hasn't increased one bit.......hold the rpm at a steady state and apply the drum brake and the actual power produced by the engine will be the same whether you are using lead or helium wheels.

Had exactly the same argument with some one in BSB when they fitted a dry clutch conversion and got about a 4bhp measured power increase..they claimed this was due to the dry clutch being lighter. Nope, the power increase is due to the dry clutch not churning through engine oil....

Wow. Didn't think the dry clutch gain would be that much. Where did I put my credit card?

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he says it's about 13.7/8 topend and about 13.5 in the middle, so could stand a bigger main jet. not bad for a 40k motor i reckon.

dont think the needles are worn, so going to leave the stock ones in.

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afr ratio, or the mixture strength. 13.5/1, or 13.9/1 parts air to fuel in weight. anything above 13.5 i would consider a bit lean, especially for racing, and into the 14/1 makes me really nervous.

in my experience (limited, i've only really done supermono tuning, but probably done 40 hours on a dyno) 12.5 ish normally gives the best hp.

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btw, the dyno operator has a sniffer which he shoves up the exhaust which sucks some fumes into a box with a wideband lambda sensor in it. This sensor is like the one in your car, but has a greater degree of accuracy.

I'm no expert, but essentially i think a narrow band just says rich, or lean, whereas the wideband says how rich or lean. Very valuable tool indeed. In fact i don't really know how you would set a bike up without one. I havnt the skill to manage without.

Old school method was a CO meter, and before that they were into plug chops. The wideband gives you a more or less instant reading. We run a dynojet wideband commander on the mono, so the bro can see what the mixture is doing at any time, assuming he isnt too busy to look!

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afr ratio, or the mixture strength. 13.5/1, or 13.9/1 parts air to fuel in weight. anything above 13.5 i would consider a bit lean, especially for racing, and into the 14/1 makes me really nervous.

in my experience (limited, i've only really done supermono tuning, but probably done 40 hours on a dyno) 12.5 ish normally gives the best hp.

So would they be ballpark figures for having switchable two maps (PC V), one for max power and one for max range? Tim Thompson had two maps on his Kwak in PB a while ago, he claimed something like 30% better mpg for the lean mapping, as far as I remember.

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just got it back - he went bigger on the mains and put in a K+N. 134.4bhp

sounds like a lot to me on standard pipes.

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