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Post Info TOPIC: Carb Gurus - Need Help
Moo


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Carb Gurus - Need Help
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So.. having some trouble getting the carb running right with any kind of open exhaust.

Bike is a 2005 Bluey, jetting is standard, 50 pilot and 147 main.

Bike runs fine with a standard exhaust, no hesitation or blips and pulls right through the rev range.

I've introduced both a motad exhaust (which runs perfectly on my raid) and an aftermarket DMC exhaust, both run with exactly the same results.

On standard jetting, it runs poorly with lots of stuttering. Probably from around 1/4 throttle to 3/4 throttle it runs bad and is very jumpy/stuttering. If you give it WOT it pulls through and runs better. Pulled the plug out after getting back and it was clean and white. Bike starts first kick with this jetting

I then pulled the carb and upped the needle to fully rich. Also installed a V05 nozzle i had lying about (i didnt notice the jet in this was actually a 145, thought it was a 147) Running as much the same but pulling the plug it was black round the edge, white in the middle.

After reading through that thumpertalk thread, and thinking about the advice give for more free flowing exhaust i bought and tried a 52.5 pilot and 150 main.

Runs even worse now, stutters throughout the range, apart from a point at about 3/4 throttle where it tries to clear. Below 1/4 it seems fine. Bike starts first kick only if throttle is WOT, plug is now black as soot. So its obviously waaaay too rich. Bit contrary to what everyone else found with the free flowing exhausts.

So thoughts now are... original jetting was much better, but not perfect. I originally thought it was too lean because the plug can out white. Thinking the 50 pilot jet was better as it started no problems at all on this. So try 50 pilot jet, 150 main jet and put the needle in the middle? confuse

Im located in the UK around 60m above sea level

 



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Malcolm, Northamptonshire. West Anglia TRF 1996 TTR 250 Raid



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hi malcolm you might think this is silly but you havent got a tight valve slightly propped because of what your saying you have done most things carb related just a thought ive been down this road before

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would try 50 /147 & play with the needle...


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 http://www.kiwibiker.co.nz

Bikes... 06 TTR250 / 09 XT660R / 1977 Montesa Cota 348 MRR / 1979 Montesa H6 125 Enduro...

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Is that without the snorkel?

On the thumpertalk page says to get rid of the snorkel.



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If your Motad runs fine on the raid, best you strip that carb and see what is in there, as you know it runs right on that. Only way to know for sure without buying and fitting lots of different parts.

Steve



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Moo


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Still has the snorkel.

Raid is running a 48 pilot and 145 main. Will swap the carb over and see how it runs!

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Malcolm, Northamptonshire. West Anglia TRF 1996 TTR 250 Raid

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