Weld n grind, Tuning help?

[mjstef]

So i bought this Hawk 250 last fall. Dumped the OEM carb for a Mikuni so i could tune it for my elevation (3,000' Western Montana riding up to 5,000') Factory jetting on the new mikuni was marginal. VERY low power. Stepped up a few jet sizes, Runs better but bogs top end. Today since the snow melted i took it out of the shed. Jumped up to a 132.5 & 25. Started right up and idled perfect. BATTERY HELD CHARGE SINCE EARLY NOVEMBER!! Anyways, STILL bogs at the top end! Here is a video. Couldn't record HWY speeds as i don't have a go-pro. Goes up to about 45, Starts to bog, Clears up around 50 and bogs bad after that. The video is in 2nd gear and starts to bog around 3/4 throttle...... https://www.youtube.com/watch?v=Z8yeR3nnvew

[mjstef]

Here is the plug after 5 miles....

[TXDSRIDER]

That looks rich

[mjstef]

That looks rich


Ran about the same with a 130 & 22.5 but was slow off the line. Just not sure where to go with this.....

[2LZ]

I'm at 3000' and I have a 115/30 in mine. About 2 turns out on the idle mixture. They run pretty well in both my Q and Hondoids. One seems a bit lean at cold start but it's brand new and not loosened up yet. Once warm, it's fine.

[mjstef]

I'm at 3000' and I have a 115/30 in mine. About 2 turns out on the idle mixture. They run pretty well in both my Q and Hondoids. One seems a bit lean at cold start but it's brand new and not loosened up yet. Once warm, it's fine.


Thanks, I'll give that a shot.....

[mjstef]

Also running Ethanol free 92 octane. Is this causing an issue? Cars will run on 85.5 at my elevation but i didn't want Ethanol in this bike.....

[mjstef]

Holy Crap!!! Put a 115 & 30 in it and it runs like a scalded ape!!!! Thing pulls a wheelie without trying! Runs flat out with no bogging whatsoever!! When it warms up i'll run about 10 miles and pull the plug. Going in for double hernia surgery next Tuesday so it will be a while. Bout froze my arse off tonight. Thanks for the help!!

[2LZ]

Holy Crap!!! Put a 115 & 30 in it and it runs like a scalded ape!!!! Thing pulls a wheelie without trying! Runs flat out with no bogging whatsoever!! When it warms up i'll run about 10 miles and pull the plug. Going in for double hernia surgery next Tuesday so it will be a while. Bout froze my arse off tonight. Thanks for the help!!
Right on! Glad to hear it!....and oh....dude....I did the double hernia thing a few years ago. It's why I was down when I messed with stripping my X-Moto that's posted here somewhere.

Free advice: Lots of recliner or I used a camping recliner. The zero gravity type you can flip way back on. Buy two large bags of generic frozen peas. They are your best friends and will bend around where needed. Stay on the Norco even though you think you're feeling alright. Good luck!!

[mjstef]

Right on! Glad to hear it!....and oh....dude....I did the double hernia thing a few years ago. It's why I was down when I messed with stripping my X-Moto that's posted here somewhere.

Free advice: Lots of recliner or I used a camping recliner. The zero gravity type you can flip way back on. Buy two large bags of generic frozen peas. They are your best friends and will bend around where needed. Stay on the Norco even though you think you're feeling alright. Good luck!!



NOT looking forward to sitting around! I grew up on a dairy farm and have always had the go go go mentality. Wife will have to keep an eye on me.....

[Weldangrind]

Ok, I'm late to the party. It has been stupid busy at work.


Glad to hear that the bike runs well with a 115 main. Next time you get a chance to ride it, do a plug chop at around 50-55mph, and see what the colour is like. I suspect you can still go a little leaner, but the colour is the key.