Hawk owners!!!!!

[hnu13]

Originally Posted by Weldangrind

When you feel like it's hitting the rev limiter, how does it behave? Like the ignition is cutting out?

this is all at 3/4-WOT btw....
it feels like a fuel problem, if i roll off to 1/2-3/4 throttle, i can rev it out more.... it WILL rev to about 8k i would guess (no tach), but i have to ease into it.

[hnu13]

Originally Posted by SlowJunk

On mine it wouldn't idle with full choke. Half choke and no choke seemed to have no differing effect. It took a bit of throttle twist and Half choke to get it to start and idle from near freezing cold. Idle RPM would vary depending on how warmed up the engine was. Acted like it was cutting out at higher RPMs.

Although not perfect for a new bike, my solution was changing the carb to the Mikuni jetting it for sea level.

Power seems to be up, starts and idles on first try with very short starter spin time, idles on full choke when very cold . Much different bike. Best mod I've made so far.

sounds just like mine. spark plug is a little white, so i think I'm lean???
its been running great, and the weather had been good lately (FloridaLife). :-)
was thinking about just jetting the pz30, now I'm just thinking about just going with the mikuni?!?!?!?

[hnu13]

Originally Posted by TXDSRIDER

My results were about the same I would have to give it gas to get it started and would sometimes have to hold the throttle. I would also have to adjust the idle screw up high then turn it down as the bike warmed. When I changed to the mikuni I set the idle screw once and haven't changed it since I just have to decide on choke position depending on temperature. On a side note first gear is extremely short with stock gearing maybe 10 mph tops.

same exact thing, i swapped to a 17t front sprocket, and i can ride first to about 20 i believe (speedo cable broke last week)???
starting process is the same though... most definitely dependent on the temp...

[kohburn]

Originally Posted by hnu13

this is all at 3/4-WOT btw....
it feels like a fuel problem, if i roll off to 1/2-3/4 throttle, i can rev it out more.... it WILL rev to about 8k i would guess (no tach), but i have to ease into it.

that sounds like a fuel atomization issue. at lower throttle levels the restricting the opening (throttle valve) increase the air velocity going through the smaller opening than when its wide open.
could also be jetting related I suppose.

[Weldangrind]

CSR, maybe a 115 main jet is better in cold weather in your area.

Perhaps you could epoxy something to the head of the Philips screw, to make it easier to turn by hand, although a fatter slow jet might negate that need.

[CSR_Sprocket]

Thanks for the advice, WeldAnGrind. I'll install 115 pilot and 140 main jets; open up the top of the air box; (like the 3x3 mod that's popular on DR-Z400s); then try using JB weld, fuel line as a mold, and silicone spray as a mold release on the 30mm clone's idle and mixture screws.

If that works I'll post photos and then transfer these ideas to the CVK32 carbs on my Ural. Maybe I can finally stop burning my fingers on hot Ural engine parts with each change in seasons (-:


As many here have written, your knowledge, experience, and insight are both valued and appreciated.

[Weldangrind]

Sorry, I meant to say 115 main jet. I edited my post above.

You could also try a #40 slow jet, but I suspect that's a little fat.

Where do you have the pilot mixture screw set?

[CSR_Sprocket]

Weldandgrind,

My mistake as well. I'm currently running a 35 pilot jet and 112.5 main jet. The idle mixture screw is backed out 2 turns.

I've been thinking to open up the top of the airbox, so maybe I'll try that first. If I still get hard cold starts (I need to use electric starter unless I'm REALLY lucky), I'll install the #40 slow/idle/pilot jet that I have on hand.

Thanks again for your help.

[Weldangrind]

Opening up the top of the airbox will introduce more air, meaning the jets will be even leaner than needed. I recommend the fatter jets first.