Higher Rev Misfires

**Melancholy67** · #1 28 Aug 2003

Hi,
I'm kind of new to this game. After 10 years of bicycle touring I've decided to move into engines and bought Dan Walsh's old XT600E. A 2000 model. It had been standing about 7 Months. I have cleaned it out, replaced the plug, oil, filters etc and cleaned out the carb. It starts well. Accelerates nicely. But at a constant 3000 revs misfires badly. Any Ideas.

Cheers George

**FredXTZ** · #2 31 Aug 2003

How do you know the revs if this one doesn't have a revcounter?
And you're not supposed to run this engine at 3000 rpm. Best is not to let it get below 3800.

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Fred, XTZ660, Holland.

**Geoff van de Merwe** · #3 31 Aug 2003

Hi George,
Have you searched through this bulletin board?
There are a few threads on XT's misfiring.
My '88 Tenere was misfiring at about 5000revs, which was a product of heaps of small problems.
Most of these are mentioned on this site,
but start by cleaning all electrical contacts incl. the earth.
Geoff

**Boxer** · #4 31 Aug 2003

Hello there - no advice on misfire, but seem to recall I saw the bike on show at NEC some time ago. It had a massive ding in the front rim. Best of luck with new hobby. I'm new to XT's too and have done a bit of cycle touring. All your old routes will be good on XT especially Highlands. Agree you should do thorough check of all electrics for a start. Also think it's ok to run at 3000rpm as long as you are not trying to accelarate, climb hills etc.

**Melancholy67** · #5 4 Sep 2003

Many Thanks for the replies.
Hoping to get a bit of time soon to have a good look at the electrics although I'll be working a little blind.
Yup the ding in the front wheel is still there. Might need a little careful attention with a hammer or even a new one. I'll have a further cruise through the site and see what I come up with.
The 3000 rpm was only intended as a guide, but it's really at any constant running speed that the misfire kicks in. I haven't been out that much since kangerooing around the streets of Cardiff isn't really my idea of fun.
Happy travels everyone

**FredXTZ** · #6 4 Sep 2003

If it's at any constant speed I would chck the connection rubbers between the cylinder head and the carbs.

------------------
Fred, XTZ660, Holland.

**Linkster** · #7 16 Sep 2009

Quote:

Originally Posted by Geoff van de Merwe

Hi George,
Have you searched through this bulletin board?
There are a few threads on XT's misfiring.
My '88 Tenere was misfiring at about 5000revs, which was a product of heaps of small problems.
Most of these are mentioned on this site,
but start by cleaning all electrical contacts incl. the earth.
Geoff

Hey there,

Was wondering if you can remember what caused your xt 600 to missfire at 5000 revs? I have a 1984 Xt 600 43F that does the same thing. It's definately electrical. I've bought a new CDI, swapped coils from my other XT 600, new plug, disconnected kick stand switch, new igniton switch and on/off switch, new battery..... all making no difference! I'm currently having my stator rewound, hoping that's it. If you have any new ideas.... help!! The bike only has 5900 miles and is very clean.

Thanks, Baron

**bacardi23** · #8 16 Sep 2009

once I found out I had the turn signals relay loose and it had already broken the outside of its casing...when it touched the frame it would make my XT misfire.... the relay on my bike is fitted with a rubber band onto the isde of the battery box behind the left seat side panel....mine is a 1990 XT600E

Vando

**Pigford** · #9 16 Sep 2009

If its at constant throttle, the carb will be running on the "pilot system" - up to 1/8 throttle approx. Worth taking the carb off & giving it a real good clean & check over. Is it all standard air box, filter & exhaust.
Dan was NOT known for mechanical empathy - (great book "These are the things that should happen to you" or sumink like that!)