the end of my tether is in sight - won't rev

[marlbororman]

oh oh, yer that would do it, but dunno if hes had the tank off or not, he said it happened soon as rec reg blew .

[benny hedges]

im not convinced either - i think this will turn out to be something annoyingly simple....

[silversixx]

Hi all, yes have checked the vac connection to the tap and all appears to be good. I too get the feeling it'll be something simple somewhere, but can't see past the fact that whatever it is was probably caused by the reg/rec failing and tazering the elastic-trickery system.

[sirch345]

I agree it would make sense for it to be something connected with the R/R failure, but I feel that could just be coincidence, but who knows.

The problem is (as you may already know) electrical or fuel faults give almost the same symptoms.

Have you pulled the carbs apart to check the diaphragms in them for a split, plus checking that the slides are operating freely Also the diaphragm in the fuel tap could have a spit in it. Also check for any splits in the vacuum hose(s). If you have a pipe fitted to the front inlet manifold (for making carb balancing easier) check that's not drawing in air anywhere too.

When was the last time you had the carbs balanced

Also check out the choke set-up is working properly, that it's shutting off as it appears at the pull-knob. It's a 2 into 1 cable afair. Be careful though with the fittings that attach to each carb, they are quite fragile.

Chris.

[MJONESY]

is it the same battery that was fitted when the reg/rec went pop? have you tried it with a different battery, may be that yours is f*****d

[Gerrit]

Hi siversixx!

I have a similar problem at the moment - Bike idles fine, pulls fine bat at 5000rpm, the misfire - similar to a rev-limiter - starts.

I have also been through all the options the past two weeks, the carbs are fine, coils replaced, plugs & leads replaced, worked through the wiring harness, can not find the fault.

The mnisfire appeared, directly after I replaced a blown headlight.

Anyway, today I put it all together again and parked it, will commute with the scooter, intil I get some devine intevention.

Good luck with yours.

Gerrit

[benny hedges]

Bike idles fine, pulls fine bat at 5000rpm, the misfire - similar to a rev-limiter - starts.

i think that's what the problem is tbh. how does the bike know you are at 10500rpm (normally)?
i think the voltage / current problems of the r/r failure somehow damaged the bike's ability to know what rpm it's at, and you get your symptoms.

i don't know how the circuitry works - phil vt is probably your man?
just a suggestion, seeing as all else seems to have failed...

[silversixx]

Hi Gerrit, hi again Benny,

yes I've read Gerrit's thread and there are definitely similarities. Sadly, like Gerrit I've reached the stage where it's taken enough time, money and effort. Everything checks
out ok from fuel to plugs to coils etc etc etc...

I'm no quitter, but I know when I'm trying to pee against a hurricane! I can afford to tinker for another couple of weeks maybe, so perhaps I'll stumble across the solution at some point. If I do, you'll all be the first to know!

[warby221]

Just to let you know about 4000 revs is the transition point for the carbs from the low speed circuit to the main jet
So I’d check for crap or water getting in to the main jet as you said it will suddenly clear and take off I’d cheek for water in the fuel first
As it’s the easiest to do
If you look at the bottom of the float chamber you'll see a nipple were you can attache a pipe
Connect a pipe to it then run it to a clear jar
On one side of the float chamber right at the bottom you'll see a flat head screw this lets you drain the carb of petrol from the float bowl
Open it and let it drain in to the jar if there’s any water it will show in the bottom of the petrol as round baubles of water (patrols basically a very light oil so oil and water won’t mix)
It also lets you see if there’s a lot of crap in your petrol

[silversixx]

Hi, have drained the carbs and even set up an independent fuel source. Made no difference. Am adamant that this is an electrical issue. Tell you what gents, I don't fancy another Honda after what this one has put me
through.

[Phil-VTwin]

Ohhh i see my name mentioned.....

The symptoms that you have described IMHO only point to 1 thing and that is the ignition advance, the 3500-4000 rpm you mentioned is the point where the engine will start to splutter if the ignition timing is static.

Carry out the tests in section 17 of the workshop manual.

[silversixx]

Thanks Phil, when you say 'workshop manual' I take it you don't mean the Haynes one (which I have)?

[Phil-VTwin]

No, the official workshop manual which you can download (the links are here somewhere!) but the haynes one may do.

[silversixx]

Interesting... Have just unplugged the switch and the bike runs exactly as it does with it plugged in. Have found the tps section in Haynes manual (page 5.6) and will now go and measure all the resistances as it advises. Everyone please cross your fingers/pray/etc !

[Gerrit]

Hi Silversixx, Just had both my coils at an auto-electrician to test them under load, They throw a spark as long as my arm, thus my coils are OK.

Discussing my problem with this guy, he mentioned that if my rev counter would drop at the point where the misfire starts it will indicate that the problem is electrical related, however, my rev counter does not drop, meaning it does not lose signal, thus in my case it has to be carb/fuel related....

Just dunno where to look at anymore, it gets plenty fuel, the diaphrams are not split, the slides move freely, the floats are fine, the needle & seats been replaced....

Gerrit