# 840 brute jetting



## 05brute91

I'm finishing up my 840 and starting to think about jetting I will be running hmf exhaust and I would like to use dyno jet but all I see is stage one kit would I need bigger jets then stage one kit offers or would I be ok with a stage one kit thanks guys


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## browland

I think stage 1 for a 750 goes up to 165. You will more than likely be fine


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## J2!

For an 840 you will be up in the 170's to 180's on jets, a stage one kit probably won't do you any good. These ar Keihin numbers.


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## Waddaman

Running 180 dyno Fr, 185 Rr mains, 2 shims under each needle, 42 pilots, dynojet hole drilled in slide with my 840 running 2 - 2" snorkels and muzzy super pro dual exhaust


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## 05brute91

What do you mean dynojet hole drilled in slide?


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## Waddaman

It's part of the dynojet jetkit but it doesn't really effect A/F ratio just throttle response.

If you want to get that 840 running right your going to need an Wideband A/F meter.


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## 05brute91

Ok I've been thinking of getting one anyway would I have to drill a hole in my exhaust to put the o2 sensor in


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## Waddaman

yea you need an O2 bung to use it.


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## J2!

You will need one in each exhaust pipe so you can tune one cylinder at a time, that's the only way to get it right. About 12.5 AF is what you want to shoot for.


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## 05brute91

Alright thanks


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## 05brute91

were did you get your 180 and 185 dyno jets at I just orde a jet kit but it goes to 165. did you get them for a diff model. I tried to find a stage 2 or 3 kit but I guess they just make stage 1 thanks


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## J2!

You have to buy individual jets. The ones that big don't come in any kit. It's all trial and error when you get to that point. I know it sucks but you will have several jets left over when it's all said and done. I have a bunch left over myself. Finally I just took mine to a dyno to have it tuned since he has ALL the jets there and I only needed two of them. LOL


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## 05brute91

Wish I knew some one who had a dyno lol but with the wide band meter I can get pretty close right?


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## J2!

Yeah you can actually tune it better with a wideband because you are making real passes with it under real world conditions and strain on the motor. With carbed bikes it just takes patience because of having to keep changing jet after jet until it's right. When you dyno it he has all the jets and you actually get some hp and torque numbers on it, that's about the only good things about it. Where are you located ?? I have a wideband.


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## 05brute91

Near Columbia sc I've been looking at buying one for awhile now do you have any advise on best brands?


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