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Random fart valve??

Old 04-16-2017, 09:05 PM
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Random fart valve??

So I did half oh 8591Hawks carb set up. (Sorry if the number is wrong.) Did not shim the needles as they are au1d. I am running moriwoki zero full titanium exhaust. Stock box and stock filter. The fart started after my rebuild. I think one of my valves has too much Clarence do to a caliper misread!! I checked after and it was too far. I may have a weak coil and its always the front which has been repaired after cct blow out last year. I do not want to check the valves until I port the spare engine. I got no shims and no gauge. I borrowed the gauges last time. I do not have my pilots yet. Stock ones. But the bike accelerates hard and 90 percent of the time she's OK. Its a super random fart that was much worse before rebuild. Carbs will be rebalanced tonight. That's all I can think of. The farts used to stall the engine at idle. Any ideas? No weak spots in the rpm up to 7000 I can't mash it because my sprocket is cooked. That comes tomorrow.
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Old 04-17-2017, 09:13 AM
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8541Hawk is the id?

I'm a nube with previous terrible carb problems. Back fires, decelleration pops and bangs, stalling at stoplights, terrible light or neutral throttle jerkyness, hard starting, long warm time to get anything close to ride able. I dunno what a VTR fart is. Do You mean the chuff sound that comes from under the tank a stop lights, often preceding a stall? Sounds like a backfire coming up the carb?

With the objective of a street able machine, not going racing.
From a 100% stock 1998 with Yoshi 3R exhaust the following changes:

1. Changed pilots from 45 to 48
2. Removed PAIR system
3. Using "bent Tab method" changed TPS @ idle from 883 to 520

I have not touched the balance or mixture screws. That is new terrain I'd like to do with an expert.

In preparation for the three above, replaced the fuel valve vacuum membrane, replaced the float needles. For me, it's perfect. Some people shim needles. I don't know which of the three changes fixed it. My guess is the PAIRectomy eliminated the popping and banging of after ignition in the exhaust and the #48 made it idle right and run right at light throttle?
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Old 04-17-2017, 04:24 PM
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8541Hawk has the best guide on getting your machine started toward smooth. I have different needles as mines Japanese. Tps is set. I still haven't bought pilots as my front tire was shot now my rear is. Lol. ( insert joke nothing else).
Lift hope in the front is blocked
Mixture is set. 2 1/4 F 2 1/2 rear.
Idle is now set to 1000r.
Should be remotely balanced but have not had the chance to make a new balancer.
No pair on this bike.
Also the engine was restricted by the intake, way smaller than usdm.
I want to try 48s but I am deeply considering expensive slide carbs as I'm used to em and im going to be porting putting in new pistonaes and crank work. Later rather than sooner. It runs good just a random small chuff. Shes pretty good at all rpm. Before shed be weak under 3000 and surge over 7000

Last edited by RedStormJ; 04-17-2017 at 04:30 PM.
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