my kat does not go above 8000rpm ?

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superfly

my kat does not go above 8000rpm ?

Post by superfly » Tue May 08, 2012 8:30 am

Hi lads,

I change the carbs this weekend, for new carbs with lovely undamaged cold start pipe.
And the choke and the starting work like a treat now, the problem is that I can not go above 8000 rpm (100km/h) which is not great :evil:

So what could go wrong inside the carbs for this to happen?

With the old carbs except for the starting problem it was up no problem, so I am a bit confuse there, any idea welcome.

superfly

Re: my kat does not go above 8000rpm ?

Post by superfly » Tue May 08, 2012 8:40 am

When riding, basically this morning I was on the motorway and I wanted to go above 100km, but I could not the bike is struggling then.

I would say it is something in the carbs as it is the only thing I change this weekend.

bobster

Re: my kat does not go above 8000rpm ?

Post by bobster » Tue May 08, 2012 9:28 am

compare the jet sizes in your original carbs, and if different to the ones in the new carbs.............swap them all over.

But i'm with Mick on giving them a good clean too...............and a check over!

callyboy

Re: my kat does not go above 8000rpm ?

Post by callyboy » Tue May 08, 2012 9:53 am

Make sure you havent got a pinched fuel pipe as well Arnaud. Maybe trapped it putting the tank on.

Pete

superfly

Re: my kat does not go above 8000rpm ?

Post by superfly » Tue May 08, 2012 9:57 am

I took them appart, and ultrasonic clean, and rebuild.

I was thinking about that just simply swap the inside of the old carbs to the new one, and try.
Maybe with 2 set I can get something working.

I am just thinking to check the float bowl I just need to put them in a bucket of water and see if it seak no?

superfly

Re: my kat does not go above 8000rpm ?

Post by superfly » Tue May 08, 2012 9:58 am

callyboy wrote:Make sure you havent got a pinched fuel pipe as well Arnaud. Maybe trapped it putting the tank on.

Pete
actually as you are saying it the fuel pipe is a bit short so the problem might start there. :roll:

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Re: my kat does not go above 8000rpm ?

Post by Katman » Tue May 08, 2012 6:55 pm

My 400 wouldn't go above 70-80 but one balance later & suddenly it revved ok & flew along at a eer good rate of knots officer.
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Re: my kat does not go above 8000rpm ?

Post by superfly » Tue May 08, 2012 9:02 pm

I did a sync after the carburator swap so that should be ok, but sure I can doubled checked that next weekend.

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Re: my kat does not go above 8000rpm ?

Post by johnr » Sat May 12, 2012 12:48 pm

check that your ht leads are screwed tightly into the coils, check that your diaphragms arent seated badly on the carb tops.
when you ultrasonic cleaned the carbs, did you remove the emulsion tubes from them? 8k sounds like the area that the bike is moving onto mainjet only, and thats where the holes in the emulsion tubes are critical.
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superfly

Re: my kat does not go above 8000rpm ?

Post by superfly » Sun May 13, 2012 2:28 pm

The ht lead are tight into the coils, I swap the diaphragms with the previous carbs so as the float, needles.

What is the emulion tube ? Sorry john I don't fully understand.

I did not retry the bike since yesterday swap I am too tired to gear up, and I have decided to stop the garage for the afternoon :-/ I need to work for the boss....

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