My turn for jetting help.

[brodzowski]

I just bought an HMF slip on with a quiet core (jeezus for bein quiet it's hella loud!) and the main jet that came with it was a 152. When this bike was delivered to me it had a 175!!!! Sounds crazy to me...

Anyway I've done the reading on here about how to set it, but I wanted your opinions on at least where to start.

The bike barely wanted to idle with a 38 pilot and would die when you snapped the throttle which instantly said to me that it was lean down there. I bought a 42 pilot and put it in at lunch and it will idle nicely now and if you gradually use throttle, it will rev up, but if you snap it, it still bogs and one time even died. Is it still lean or is this an idicator of the needle clip needing changed? When I do rev it I see smoke that I didn't before. It HAD like I said a 175 and I dropped it to a 168 which is as low as the dealer had. Next step? Put the 152 in?
I need a little detail on the mixture screw too. I've read it but it hasn't really been clear. Something like if you make it to 3 turns you should go up a jet and under 1 down one I believe.

I have a stock motor as far as I know with an open airbox lid and the HMF slip on.
I'm far from giving up, but this is my first attempt at getting it right myself. As you all know mine's the one that fell off the trailer and I'm still waiting for parts so I can't ride it yet either. It's just on jackstands.

Any suggestion where to start?

[atvmaster0927]

Start at 156 main and go from there. Jetting is all trial and error. Your main jet with a 168 is WAY to high and is most likely why it is dieing.

You really dont need to mess with the needle. All it does richin/lean slightly. I'm sure someone else can elaborate much more for you.

[zwark]

www.jetsrus.com get an assortment of jets. a 40 pilot jet should work for you if the 42 is too much. try a 155, 158. that should have you running good.

don't forget, fine tuning your carburetor should also be done, rich-en the needle jet by one clip and try a half turn on your fuel screw at a time. Be careful with the screws on the float bowl, they are brass and strip VERY easily. I suggest buying stainless steel screws from the hardware store, bring the screw into the store and the clerk should be able to match it for you.

[Wheelie]

Are you revving it in neutral? If you're stabbing the throttle in neutral, that's an incorrect indication of jetting. Tune the machine by how it runs under a load, not in neutral.

[brodzowski]

Originally posted by Wheelie
Are you revving it in neutral? If you're stabbing the throttle in neutral, that's an incorrect indication of jetting. Tune the machine by how it runs under a load, not in neutral.

I WONdered about that. Yes I was. Is it enough load to just have it in gear? Like on stands? Or do you actually need to be riding it? And to zwark, that's exACTly what I did today. It's going to be another week before I get them of course but I did order the set and about 4 pilots too. Thanks for the heads up. I guess I can't really chase this thing until I get my parts on.

[Wheelie]

Riding the machine or a dyno is the only way to tune. In gear, on stands is not enough load, just because the engine falls flat when the throttle is stabbed in neutral doesn't mean the jetting is off.

[brodzowski]

I knew there was a reason I come here. You guys are a wealth of information. I don't have access to a dyno anywhere near however, so I'm going to have to wait until I can get my ride back in one piece. Hopefully my stem comes tomorrow.