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Not running happy wot, blah blah not brapp brapp

322 Views 11 Replies 4 Participants Last post by  TrailBurner
Throwing this out there cause I'm outta thoughts.
86 stock bore, drag port, boysen reeds, pwk 40, 160 dgh-4, 110/klutz, k&n, 01 cr ign.
So..., fired it up Friday, 1st time in 5-6 yrs. Ran great til half throttle then ran like plug junk, usual feel. Then thought maybe pipe wasn't hot enough, didn't give the hit. I'm like wtf, the R never does this.
So at the track for test n tune today, new plug, ran 3 4 runs, all the same crap. But never backfired exhaust or intake. So its like its choking somewhere , kinda sound. Bike always wanted a 160 main, I checked reeds there new, checked exhaust not plugged. Pulled carb, area from carb boot to boysen intake... more fuel puddled then I'd like. Not real happy w 160 psi, but that was cold. My inline coolant temp gage was 100 140 150 maybe, that is on the lower rad hose to water pump.
I'm just stumped, all the simple normal fuel air spark is where it was 6 yrs ago when it last ran. Sucks looking like a chump at the drags. Trying to represent the R.
If you guys made it through this post, good job. If yeah got any ideas that I over looked..., going to order new rings... just cause, looking into cylinder from intake n exhaust I didn't see anything concerning. But going to track Sunday to take my 2 quick loses n fix for following race. May work on it in the morning, so throw me ideas.
Humbled @ the moment, not frustrated. TB
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A few things I would check
Air filter
Fuel flow
Spark
Pull stator cover and check the flywheel, stator and pickup

When you stored it, did you leave gas in it? If so you will want to clean the tank, petcock and carb really good.

Best regards
-Jason
Only thing I didn't due was pull flywheel off, look inside. Last night I just pulled stator cover off n looked. I have a couple hrs before I head out.
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Pulled flywheel, all good there. Thinking copper head gasket is leaking inboard. Pulled the plug, showed signs of washing. Didnt feel like draining coolant and re sealing at 6am. Will confirm when I get home n tear it down. Should've started it last weekend and found the issue. Well it will be a short race day today, be home by 3pm. Got a few good pics of Mount Washington on the way.
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Stock bore...40mm pwk carburetor....dayum I'm just gonna throw this out there....I think you might try a smaller carburetor...like 36pwk. I have a 350 pv engine and it uses a 38mm. Just a thought
Head gasket leaking inboard, as I thought.
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Stock bore...40mm pwk carburetor....dayum I'm just gonna throw this out there....I think you might try a smaller carburetor...like 36pwk. I have a 350 pv engine and it uses a 38mm. Just a thought
With a 36mm carb he'd loose every time on the big end. Even though its a small bore its drag ported & with that 40PWK it most likely uses all of it on the big end..... I have a 38AS on my wife's R with an unported oem cylinder & some other bolt on's. It makes great torque down low & runs amazing in both woods & dunes.
With a 36mm carb he'd loose every time on the big end. Even though its a small bore its drag ported & with that 40PWK it most likely uses all of it on the big end..... I have a 38AS on my wife's R with an unported oem cylinder & some other bolt on's. It makes great torque down low & runs amazing in both woods & dunes.
Correct, drag port likes the 40.
After further review, see the cracks around water jackets ? Wtf, front n front right exhaust side. I pulled apart last week, checked head gasket, few lil half tic tac size rust spots on it. Have 2 new on order, new head gasket ain't gonna due shit if its cracked beyond seal area. Anyone have this happen or seen the issue? Casting ? Really can't snag w fingernail. Not inboard of coolant passage, just top. Whats the deal, issues.
Thru old metal gasket on to see whats up, could just be imprint from gasket... yes?
Thru old metal gasket on to see whats up, could just be imprint from gasket... yes?
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Also seems like holes are tight, cupping from head studs.
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