Help with proper jet size for Mikuni on hawk

[xposur]

Im 640 feet above sea level in the midwest., I read thru the forum for hours and everyone is saying 115 main 30 slow but would there be more gain with running a richer jet say 120 or higher?
or a 110 main ? (Leaner meaner?)

I plan on keeping the air box with modding the inlet. Keeping the exhaust stock so its quieter on the trails. I do more off roading than street so the more wheelie, hill climbing power the better.

[mq1991]

Originally Posted by xposur

Im 640 feet above sea level in the midwest., I read thru the forum for hours and everyone is saying 115 main 30 slow but would there be more gain with running a richer jet say 120 or higher?
or a 110 main ? (Leaner meaner?)

I plan on keeping the air box with modding the inlet. Keeping the exhaust stock so its quieter on the trails. I do more off roading than street so the more wheelie, hill climbing power the better.

When I was tuning mine, I found that going to a 125 from a 120 caused it to bog at higher rpm, and going down to a 115 cleared it up completely.

I also found the 20 slow jet worked best for me as well. I tried the 30 but couldnt get it to idle correctly.

Lots of power though! I can do first-second gear wheelies, and it tops out at 64mph (GPS) with the 17t front sprocket.

Play around with it, try going up and down and take it for a ride and see what works best for you. I bought a pack of jets so I could try all sorts of em.

Good luck!

[newrider93]

Originally Posted by xposur

Im 640 feet above sea level in the midwest., I read thru the forum for hours and everyone is saying 115 main 30 slow but would there be more gain with running a richer jet say 120 or higher?
or a 110 main ? (Leaner meaner?)

I plan on keeping the air box with modding the inlet. Keeping the exhaust stock so its quieter on the trails. I do more off roading than street so the more wheelie, hill climbing power the better.

If you buy a 30mm mikuni as I did try the jets that come in it before you start messing with replacing them. I bought a jet assortment for mine but I found that my bike runs fine with the jets it came with. It won't hurt to go with a larger main jet but you may find that your bike will run fine with the jets that are in it.

[xposur]

Originally Posted by mq1991

When I was tuning mine, I found that going to a 125 from a 120 caused it to bog at higher rpm, and going down to a 115 cleared it up completely.

I also found the 20 slow jet worked best for me as well. I tried the 30 but couldnt get it to idle correctly.

Lots of power though! I can do first-second gear wheelies, and it tops out at 64mph (GPS) with the 17t front sprocket.

Play around with it, try going up and down and take it for a ride and see what works best for you. I bought a pack of jets so I could try all sorts of em.

Good luck!

Thanks! Did you notice anything going to a 110?
right now I can only do wheelies from a stop and clutch pop at 5 ot 6k

Btw your not too far away from me. I actually ride up to your neck of the woods, taking the Des Plaines River Trail all the way from Des Plaines. Its not exactly legal but I ride at night to minimize getting caught, lots of fun. Other than that I take it to the Rockford off Road park Rocky Glen.

[xposur]

thanks, I will try them out as well.

[mq1991]

Originally Posted by xposur

Thanks! Did you notice anything going to a 110?
right now I can only do wheelies from a stop and clutch pop at 5 ot 6k

Btw your not too far away from me. I actually ride up to your neck of the woods, taking the Des Plaines River Trail all the way from Des Plaines. Its not exactly legal but I ride at night to minimize getting caught, lots of fun. Other than that I take it to the Rockford off Road park Rocky Glen.

Haven't tried yet, I was really happy with the way the 115 felt so I havent gone down farther. That being said my idle is still iffy... it wont idle off choke until its completely warmed up, then its good for the most part.

It should be able to power wheelie if your crawling along at idle speed or so and just gun it. Im going to make some videos about my bike when I get my new headlight assembly back. What is your current setup?

Nice! yeah I live about a minute away from the Des Plaines Canoe Launch off of Wadsworth road. I havent been brave enough to try those trails yet We should meet up sometime. I commute to Palatine for work Mon Wed and Fri if your close by there.

I may have to join up with you going to that off road park, sounds awesome!

[xposur]

Originally Posted by mq1991

Haven't tried yet, I was really happy with the way the 115 felt so I havent gone down farther. That being said my idle is still iffy... it wont idle off choke until its completely warmed up, then its good for the most part.

It should be able to power wheelie if your crawling along at idle speed or so and just gun it. Im going to make some videos about my bike when I get my new headlight assembly back. What is your current setup?

Nice! yeah I live about a minute away from the Des Plaines Canoe Launch off of Wadsworth road. I havent been brave enough to try those trails yet We should meet up sometime. I commute to Palatine for work Mon Wed and Fri if your close by there.

I may have to join up with you going to that off road park, sounds awesome!

Right now the bike is all stock besides, bark bashers, crash bar, LED headlight. Yea we can meet up sometime and you can join in a night trail run one weekend. Its a nice 2 hour ride on the trails. Only have to cross 2 roads, Dundee and HalfDay the rest are under bridges or bridges.

[2LZ]

Originally Posted by mq1991

When I was tuning mine, I found that going to a 125 from a 120 caused it to bog at higher rpm, and going down to a 115 cleared it up completely.

I also found the 20 slow jet worked best for me as well. I tried the 30 but couldnt get it to idle correctly.

Lots of power though! I can do first-second gear wheelies, and it tops out at 64mph (GPS) with the 17t front sprocket.

Play around with it, try going up and down and take it for a ride and see what works best for you. I bought a pack of jets so I could try all sorts of em.

Good luck!

I have a 115/30 setup in my 30MM Mikuni on my 229 (250) 167FMM motor @ 3000 feet elevation and it runs very well, but I also have a K&N breather and an FMF TC2 pipe on it to clean up the breathing. It does seem a little rich just off of idle with the 30 pilot but I've been able to adjust that out with the mixture screw. I may go back and try the stock 20 pilot just to see if it cleans up a little off of idle.....but as I recall I have a lean "pop and sneeze" with the 20 just a little throttle. At WOT, the 115 main runs great!
Too many bikes, too many jetting combos to remember......
I really think that the 115 main/30 or 20 pilot jetting will allow you to run pretty well in a variety of elevations.

[xposur]

thanks for your input

[Weldangrind]

Originally Posted by 2LZ

It does seem a little rich just off of idle with the 30 pilot but I've been able to adjust that out with the mixture screw. I may go back and try the stock 20 pilot just to see if it cleans up a little off of idle.....but as I recall I have a lean "pop and sneeze" with the 20 just a little throttle. At WOT, the 115 main runs great!

You can really dial it in, if you're so inclined. Slow jets are available in 22.5, 25 and 27.5 sizes.

[2LZ]

Originally Posted by Weldangrind

You can really dial it in, if you're so inclined. Slow jets are available in 22.5, 25 and 27.5 sizes.

I may end up doing this and getting a handful of jets to play with but you know how it is with these CG motors Weld... Don't make any permanent plans until it's broken in. I'm sure in another bunch of hours, it will run completely differently!

[xposur]

I think im going to start with a 127.5 pilot jet and get a 110, 115, 112.5 and 117.5 main and see which one works the best. Might end of getting an exhaust if I find something that works for these hawks.

[2LZ]

Originally Posted by xposur

I think im going to start with a 127.5 pilot jet......

That may be a bit on the fat side, especially with a stock exhaust. I have fatter jets in Q (a 127.5/35) and it's just a 200cc..but it also is an OHC with a CV Mikuni and a FMF TC2 and is much hungrier than the CG Hondoid motors. These CG motors must be cammed very mild.