Aug 27, 2022
1
0
Hi,

I bought this bike last year as a basket case and completely restored. New crank, stage 2 hot cam, high comp piston. new head and valves . It is running fairly well now at 25 hours but I am still chasing some tuning problems. Follow is list of symptoms


1. bog on throttle snap - not as bad as other bikes I've had with these carbs (DRZ400E) - but noticeble. If I adjust the fuel screw per factory specs - the bog is worse. I typically have to richen it up. I have noticed a bog on a heavy load - like rolling the throttle on in too high a gear - OK I am an old man and I was riding it like I rode the DRZ400 I used to have . . . I have to shift more with this bike . . . I don't do this anymore . . . . . but I wonder if that is a clue . . .

2. It is super sensitive to temp changes. The last time we were out, half way through the day I had to lean the fuel screw out because it stopped idling

3. Sometimes out of the blue I get a surge. I came off the track one day and it was doing this . . . I goosed it a couple times ad the idle went back to normal. the idle seems to hang at times. I sprayed starter fluid on the intake boot to check for an air leak - I observed no rpm change

4, Oh and this is a good one - sometimes I start it on the stand and lean it over a bit to get it off and gas starts coming out of the overflow hoses, the rpm goes down - and it will stall. No leakage when straight up though. I set the height at 8mm per the specs - even used a float level checker,

5. I feel like I have the hot start drill down - now if I stall it, I pull the HS lever a bit and crack the throttle and it roars to life. But it will flood easy. I can start it now because I have a drill. But my son, who could kick start a stop sign actually has difficulty with this.

Carb / work

It is a 2004 carb

- Cleaned
- JD Jeting kit
- replaced vacuum plate and gasket
- R/D flex jet
- billet hot start plug and new hotstart

Something odd that I just noticed - AC pump shoot toward SIDE of the carb

Current jetting

-42 pilot jet
-remote fuel screw - between 1 3/4 - 2 turns; in the ballpark - it runs when I pull HS lever
-175 main jet
-JDJets blue needle - raised on notch from what the recommend - experimenting to try to remove what I percieve to be a lean bog
-wired AP with a boyen floatbowl


Atmoshperic condition
- 200 feet above sea level
- temp ranges recently - 81 to 100 degrees

I have been in and out of this carb multiple times and have run out of tuning ideas. I have the curent parts on order

- mid body gasket kit
- float
- emulsion tube
- AC pump rebuild kit

Does anybody have any other ideas?

Thanks
 
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