3 brown 1 black

[bellucci]

I have been to the drragstrip several times this month... I have a mystery miss in #4. Bike comes off the line good, then seem to run on 3 for a short time. Then it seems to catch on all 4. Then the unicycle ride starts. I have pulled the plugs and the black one is always #4. The question is... is it carb or electrical... The bike has a Dyna ignition and rev limiter. The carbs are flat slides... Could float height make #4 run rich? I am going to the track tomorrow with a fresh set of plugs... Any comments would be helpful from the usual suspects(Trip,Blower,Ray,you guys know who you are...)
Curt

[SqDancerLynn1]

float height could make a difference, swap plug wires on 1 & 4 see what happens

[bellucci]

Will do...

[blowerbike]

radial slides are drippy- leaky but great/powerful carbs.
so it will idle on 4 cylinders no problem?
or is it dead on 1 cylinder then picks it up at WOT?
are the carbs sink dead on?
i don't believe electrical..
if you could borrow a set of even jet kitted factory carbs and see if the problem is still there.
if it is then i'd check the #4 hole/valves/leak down/compression check ect..

[bellucci]

It idles on 4 then under hard throttle 3 and then seems to clear up at 10000 rpm... Sync is suspect, but have no gages, so I am going to check float height, swap coil wires and beat on it tomorrow. What is the accepted float height for these carbs if you don't mind? Also the last time I went, it was 95 degrees with 90% humidity.. thanks for the response...
Curt

[blowerbike]

you don't sink these with gauges.
these are bench sinked.
if you need to know how to check just ask or check with ray.
this is really easy to do and if you pop them off you will know right away if they are close enough or not.

i'm not sure on the measurement of the float height but be careful...you could end up with a starvation problem.
drain each bowl into a beaker and write down the cc's..
compare all 4 bowl volumes.
these carbs tend to over flow from time to time....just there nature.

[bellucci]

Thanks for the info.. I have noticed they tend to dribble once in a while. When I have set the float height, I will eyeball them for sync...and if it isn't fast enough, I am coming to your neighborhood this winter...
Curt

[trippivot]

a plug wire can cause an intermittent miss like you are describing

I'll let you use my carbs and we can narrow it down between electrical or fuel delivery.

anytime you want to come over you may. I have everything we need to get that 1 cylinder hitting..

[bellucci]

Thanks Trip... I just replaced one plug and checked the other cylinder and I think it is the plug wire... Why don't you come to the track tonight? We will be there...
Curt

[bellucci]

11.7 at 122 mph with 1 cyl. coming in and out... then the tach and gear indicator died. All plugs are firing and the are brownish. Got home and found fuse blown marked signal... Maybe Dyna S signal generator gone bad?...
Curt

[TheCafeKid]

11.7 at 122 mph with 1 cyl. coming in and out... then the tach and gear indicator died. All plugs are firing and the are brownish. Got home and found fuse blown marked signal... Maybe Dyna S signal generator gone bad?...
Curt

Nope. That wouldn't be it at all. The signal fuse controls your gauge cluster lights, tail light, tach (on your bike) and TURN signals/running lights and horns. Check your wiring. Something is touching the frame or grounding out against something. Completely different circuit than ignition.

[trippivot]

you psudeo tuners don't know crap. carb problems are a 1 way street-period.

I showed up only to see you taking it home in the truck. had a beer and went home

[blowerbike]

you psudeo tuners don't know crap. carb problems are a 1 way street-period.

I showed up only to see you taking it home in the truck. had a beer and went home

where's the bellucci at?

[trippivot]

cutting a new plug wire so he can have a 4 cylinder rocket

[bellucci]

Trip,
Sorry I missed you... I am coming to your house Sunday morning to have breakfast of electrical 101...
Blowerbike,
I was at Union Grove Wi. Great little drag strip... Saw a car run 1.1 in 60 ft. Wow...
Curt