Vtr firestorm problems

Need advice on which oil to use or which tyre best suits you? Share your topic and get help here.
Collywog19
Posts: 108
Joined: Thu Jul 24, 2008 9:21 pm
Location: Durham
Contact:

Vtr firestorm problems

Post by Collywog19 »

Firstly Hi guys/gals

hope you can help

Vtr started miss firing etc other day, running on one cylinder, i got home, let it cool down, then had to go out again after to fit new chain+sprockets.

Did over 40 mile trouble free, loving it!

got up for work next day, rode in fine.

On way home, it started misfiring again :(

Had to go out to pick a jacket up, running on one cyl below 6k rpm, after 6k rpm, it would jump into life. and run as normal...

Now ive changed plugs, had carbs off etc and still running weird.

CDI? or any other ideas?

I have had no rev counter ever, i think this is down to cdi , as i fitted new gauge parts etc.

Any help would be appreciated. If only i could get a cdi to test it with lol

Thanks

Colin
Bikes ftw!
User avatar
Stratman
Posts: 2656
Joined: Mon Dec 01, 2003 10:55 pm
Location: Norwich
Contact:

Post by Stratman »

Check the plug leads for splits in the rubber gaiter. Does the problem happen after rain/washing,'cos that would point to the plug leads in my experience.
Two bikes, still only four cylinders!

Image
Collywog19
Posts: 108
Joined: Thu Jul 24, 2008 9:21 pm
Location: Durham
Contact:

Post by Collywog19 »

Been bone dry here for days. red hot weather

Both plugs have a very healthy spark.

Just bought a CDI to try, atleast it'll rule it out if it dont work, but im suspect it is the CDI.

Thanks
Bikes ftw!
User avatar
warby221
Posts: 866
Joined: Fri Jan 05, 2007 7:42 pm
Location: lancs

Post by warby221 »

If like It sounds it happens after the engine gets hot it could be some thing braking down with the heat off the engine and that’s usually some thing electronic
Mind you I would have a check of all the earths first could be some thing that simple
Image
its big----- its red ------its throbbing and it’s a thousand CC
Collywog19
Posts: 108
Joined: Thu Jul 24, 2008 9:21 pm
Location: Durham
Contact:

Post by Collywog19 »

Ok thanks guys

Ill check the earths over tonight

Any ideas where they are? thanks again, being a big help

Colin
Bikes ftw!
Collywog19
Posts: 108
Joined: Thu Jul 24, 2008 9:21 pm
Location: Durham
Contact:

Post by Collywog19 »

Just fitted the new cdi, still the same!

Swapped coils over, still the same cylinder that isnt running properly.

Running out of ideas here, could it be the smaller square cdi box?

Ive had the bike stripped , wd40'd all connectors etc etc.

I have no rev counter, even tho i fitted new clock parts, so dunno why this is.

Gonna have a long hard study of the wiring diagam etc.

Checked that the vaccuum is working, which it is, and tested tank, which is letting fuel out fine.

:(

Thanks from a very unhappy colin lol
Bikes ftw!
Beast
Posts: 232
Joined: Sun Apr 25, 2004 8:49 pm
Location: Brighton, UK

Post by Beast »

No rev counter? Does the speedo play up as well not registering properly?
Collywog19
Posts: 108
Joined: Thu Jul 24, 2008 9:21 pm
Location: Durham
Contact:

Post by Collywog19 »

speedo is 100% fine!

Caps have been changed also. I have 4 bikes so changing bits n bobs is fine.

Im totally at a loss here

ignition pickup?

im totally gutted, been lovely weather too and ive just seized my 2 stroke today lol :(

Colin
Bikes ftw!
User avatar
warby221
Posts: 866
Joined: Fri Jan 05, 2007 7:42 pm
Location: lancs

Post by warby221 »

If the Speedos ok but the rev counters playing up it would suggest a problem on the ignition side of things could be anything from the ignition switch to one of the cdi units (there’s two of them)
You need to work though them methodically and don’t assume a now or untested part is working ok
My best guess at the moment with what you have written is a bad connection on one of the terminals or even a broken wire some were
Image
its big----- its red ------its throbbing and it’s a thousand CC
Collywog19
Posts: 108
Joined: Thu Jul 24, 2008 9:21 pm
Location: Durham
Contact:

Post by Collywog19 »

Ive replaced the bigger cdi thing, gonna get the smaller one next to try, Just wish i could borrow someones instead of buying one then it not solving problem.

Ringing a V-twin specialist near me tmoro and see what he has to say.

I had the bike stripped naked, checked wires etc.

Col
Bikes ftw!
User avatar
sirch345
Site Admin
Posts: 22395
Joined: Mon Aug 25, 2003 10:35 pm
Location: The West Country.

Post by sirch345 »

I'm inclined to think it is an electrical problem as Warby says.

But then again electrical and fueling problems can give almost identical symptoms.

One thing that has not been mentioned is checking the diaphragm in the carb for a split or hole, obviously in the carb for the cylinder that's giving the misfire.

You did re-fit the TPS (throttle position sensor) when you had the carbs off I take it :?:

Did you remove the float bowls when you had the carbs off, or even just drain them :?:

Chris.

PS. What's puzzling me is the fact that it will fire properly above 6,000 rpm and not the other way around.

PPS.Had the bike been standing and not been started for a long period before this problem occurred :?:
User avatar
Stratman
Posts: 2656
Joined: Mon Dec 01, 2003 10:55 pm
Location: Norwich
Contact:

Post by Stratman »

Could it be the old vacuum pipe issue? The fuel tap diaphragm could be perished/holed, meaning only at high revs might there be enough vacuum to suck the fuel through properly?
Two bikes, still only four cylinders!

Image
Collywog19
Posts: 108
Joined: Thu Jul 24, 2008 9:21 pm
Location: Durham
Contact:

Post by Collywog19 »

Cheers lads.

I wombles the TPS when i took them off, the spring shot out never to be seen again lol

new one on its way.

I had the bowls off etc.

Smaller cdi box should be here tmoro.

It hadnt been standing at all been used constant for past 6 month.

I checked the vaccum and its spot on. Pisses fuel out everwhere lol

I'll let u all know how i get on tmoro if cdi arrives.
Bikes ftw!
Collywog19
Posts: 108
Joined: Thu Jul 24, 2008 9:21 pm
Location: Durham
Contact:

Post by Collywog19 »

Ps.

Even with or without TPS it had these problems.

just to let you know lol

Colin
Bikes ftw!
Collywog19
Posts: 108
Joined: Thu Jul 24, 2008 9:21 pm
Location: Durham
Contact:

Post by Collywog19 »

And its still broken :(

lol
Bikes ftw!
Post Reply