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Fire-medic

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An easier read. That's about what I'd expect for those mods. You should try some 147.5 Mikunis for main jets and try again, I bet you will be happy with the results. People should look at the RWHP and not 'at the engine.'

VMax A dyno.jpg
 

carrizog60

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Thanks for the help on the pic.

Operator dais it was a bit rich on low rpm but fine at high,shoudnt bother to mess with it...
More than 120rwhp is good for me,thats at sea level. Bit disapointed about he letting go the gas too soon,i bet i could see some more hp.
Just for bragging 😅
 

Fire-medic

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I don't know how-expensive the carburetor brass is there, but if you like it now, going from the (I expect) 152.5 stock jetting (though I've seen mention of European jetting being 150 main jets, Mikuni sizes) to 147.5 should provide you with a seat-of-the-pants difference, to-be confirmed by a dyno repeat. Is your bike a European model or a USA import?
 

carrizog60

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It has a canada sticker on the frame so i guess import model.
I am from portugal and it was bought new from the dealer,dont know were they source them.
Cant remember what jet sizes i got,despite cleaning them 3 times😅
 

sdt354

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4-1 hindle with shortened can, uni foam filter,raised Y ,stock jets.
Operator let go a bit soon as i kept saying to be carefull about her not having rev limiter 😅
Good numbers, but surely you left a few hp shutting down early. My numbers increased right to 9500, if I recollect. All subject to the dyno being used of course.
 

carrizog60

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Good numbers, but surely you left a few hp shutting down early. My numbers increased right to 9500, if I recollect. All subject to the dyno being used of course.
Yes,i believe it would pass the 145 factory declared.
Have a 190-50-17 on the rear,dont know if it helps on the power losses
 

Fire-medic

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Yes,i believe it would pass the 145 factory declared.
Have a 190-50-17 on the rear,dont know if it helps on the power losses
I believe you're optimistic on what you expect out of this. The factory 145 HP is not RWHP, actually, it's at the crankshaft. The highest stock RWHP I ever saw in the magazines was 119, and most were lower. You do have a full exhaust, and jetted properly that should be good for something like 10-15 additional RWHP, but the only way you're gonna get 145+ RWHP out of it is with more displacement and some $$$ internal work, or a power-adder like NOS, supercharging or turbocharging, which could exceed that. There used-to be a database on one website for the VMax, where people posted their builds, and their results. Most guys with full exhausts and jetting were somewhere in the low-mid 120's. But, you never-know, maybe the prior owner built a stout engine, the PCW Tourmaster 1500's are known to go well above 145 RWHP, and I'm sure Sean Morley can tell you about some of his builds.
 

02GF74

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That's 30% loss, a quick search shows 15% to be a figure touted, presumably shaft drive isn't doing any favours.
 

Fire-medic

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That's 30% loss, a quick search shows 15% to be a figure touted, presumably shaft drive isn't doing any favours.
I know, it sounds like a lot. I have a bunch of magazines in the library and not a one of them where they actually did dyno runs, is above the figure I quoted. I think an average value on a Dynojet 250 dyno is going to be about 110 RWHP 74 ft/lb torque, for a stock bike. Ask Sean. See what he says.

The magazines are on here, in prior threads.
 

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