4th and 5th hesitation

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Aug 13, 2013 | 07:24 PM

inkslinger73

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From: saint john ,nb,canada

4th and 5th hesitation

86 fxr Revolution performance 85"big bore kit with stock heads,andrews ev46 cam,andrews easyadjust push rods,CV carb with 45 pilot 185 main jets,cvp volocity needle,cvp spring,diaphram drilled to 1/8,A/F ez adjust 2 1/4 turns out,Dynatec 2000 ignition module and coil,set to single fire,curve 3 timing,and 6500 RPM limit,S&S stealth breather,and 2" mac performance drag pipes with the baffle still installed,plugs are a nice tan with rear plug a bit darker closer to brown,91 octane fuel..My problem is I can't for the life of me get rid of this hesitation in 4th and 5th gear.It only happens if I crank on throttle but if I ease it ever so "slowly" it doesn't do it at all.I have tryed everywhere to find info with no luck.Local shop had it for a couple days and claimed it worked fine(GO FIGURE) and couldn't explain why I might be having this issue.Do I have to adjust my static timing different than stock 35 degree?Plugs are telling me my carb is set proper.no carb popping quick responce from 1st to 3rd.I have been told over the years to hold it wide open in 4th or 5th than let off 1/8 to see what my main is doing but being a fresh rebuild I am concerned about the high RPM.Any info on where to start my search greatly appreciated.Thanks in advance.

Aug 18, 2013 | 01:38 PM

inkslinger73

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From: saint john ,nb,canada

bump!

Aug 19, 2013 | 07:30 AM

miacycles

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From: Bluffton, South Carolina

Put the stock spring back in and try to find a stock slide. We've found that drilling the slide and a lighter spring can cause a hesitation in higher gears because the slide is farther open than it should be at any given rpm. The slide is supposed to act like vacuum secondaries on carbuareted cars, only opening when you have enough vacuum for the engine to perform properly. The lighter spring,etc. will give you a little better dyno numbers, but you don't ride on a dyno. Hope this helps.
John

Aug 19, 2013 | 04:33 PM

inkslinger73

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From: saint john ,nb,canada

Thanks for the reply.I just ordered one today.ill let ya know in a few days if it remedied the problem.Sounds about right though.Thanks again

Sep 7, 2013 | 09:55 AM

inkslinger73

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From: saint john ,nb,canada

UPDATE.the hesitation is now gone.Thanks miacycles.Bike works awesome"along the coast"i live right on the bay of fundy coast.had it out on the weekend and decided to go inland(higher elevation,about 10 degrees hotter) bike worked perfect while cruising along,ended up havin to crawl along(about 20 mph) a 20 mile stretch of new chipseal/road crew on the road.bike didnt seem to be heating too bad but when I gas it throttle to get back up to speed limit on good road it was stumbling on wanted to stall.My buddy behind me noticed a single puff of black smoke from both pipes than she stalled.started right back up but would stumble and shutter once i started to release clutch than die again.started right back up second time so I shut it down with kill switch and it started to diesel for a couple seconds after switched off and back fired.I waited about 15 min tried again started and worked fine.we ran about another 50 miles no problems.Now every once and a while on shutdown either with kill switch or key it will diesel for just a few seconds.Noticed my pipes are starting to turn a purple/blue at the heads,and a **** yellow/gold down to the bottom turns.Any help appriciated.

Sep 7, 2013 | 06:17 PM

miacycles

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From: Bluffton, South Carolina

You were hot and possibly had a little too much heat in the carb, etc and were just short of vapor lock, or have an air/vacuum leak. Whenever you are stuck in traffic care must be taken not to rev the bike. Every time you rev the bike while standing still you generate a little more heat. these are air cooled beasts, so sometimes it's a good idea to just pull over and let things cool down. The dieseling can be from slightly high idle speed, hot spot in the cylinder, plug too hot, or an air leak. Hope this helps.
John

Sep 7, 2013 | 07:28 PM

inkslinger73

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From: saint john ,nb,canada

so I checked for leaks using a propane torch(not lit of course)no change in idle,idle set around 900 rpm.always had air flow even though 20 mph 3rd gear idle speed maybe 1500 rpm max,never sat or reved engine.I just want to make sure its not too lean?Strange that I can idle around all day close to the coast with no issues.Thanks again for the help