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Post Info TOPIC: Rough running-No Mid range power-Bogs Down in top- PROBLEM FIXED


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Rough running-No Mid range power-Bogs Down in top- PROBLEM FIXED
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My bike was running rough and lacked power so it was time to sort it. When I bought the bike it always felt like it was not running properly although Ive not had it long. In the low gears it would pull ok but not correctly, and when in mid revs would surge and lack any constant power delivery. Top didn’t really exist as it would bog down I would need to change a gear down to get anywhere. Riding along the dual carriageway it was painful as I couldn’t even keep a steady 60mph.

 

I tried:

Different carb with different jet size

Moving the clip on the slide on old carb

Cleaning the carb

Moving clip trying every different position

New plug

No air filter ( to test running)

New air filter

A brand new carb with 6 miles if that use

A new standard exhaust

STILL NO DIFFERENCE.

 I must have removed and refitted the carb 15 times.

So fitting everything back to standard that eliminated the carb and exhaust it was time to look elsewhere. With the rocker cover off it then became apparent the cams where not in line. Setting the cams properly (follow the excellent TTR guide) assembled the bike and took it for run.............................................................................................

 

Problem solved it runs a lot sweeter and even pulls in top gear! I reckon I was running on 2/3 rds of rough power delivery before.

A massive thank-you for all the help on here and from knowledgeable people happy to share the solutions. So if you have the same running issues and its not the carb etc its worth the ten minutes to check the cams. Mine is an R reg White OE.

Out riding tomorrow morning!biggrin



-- Edited by Mike Wright on Sunday 26th of May 2013 09:06:52 PM



-- Edited by Mike Wright on Sunday 26th of May 2013 10:45:52 PM

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I am glad you got your TTR sorted before being tempted to put a match to it Mike!

Your symptoms did point to a carburation or fuelling problem so you started on the obvious.

As your TTR suffered with these problems since you got it, I am thinking that the previous owner had the cams off to adjust the clearances and put them back one tooth out. I think this can be explained by the flywheel not wanting to stay at TDC because of the strong flywheel magnet which moves it off the mark. I get Mrs TTR to hold the flywheel whilst I get the cams right wink

Hope you have a good ride today and the TTR runs well for you.

Brian

 



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I am the new owner of this bike and it still suffers a bit with a what feels like a fueling problem. It stutters a bit, especially when running at speed on the road and still feels a bit rough in normal running. While when I bought it Mike gave me a few pointers I have since checked the fuel consumption and I am only getting about 56mpg and also I have noticed a fuel smell from time to time.
I haven't checked the plug yet but could it be getting far to much fuel instead of not enough? If so any ideas on what to look at now?

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why did you say diaphragm/pilot jet? confuse those are two seperate entities?



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TT-R250M wrote:
yamaha42 wrote:

why did you say diaphragm/pilot jet? confuse those are two seperate entities?


 Why are you talking to yourself?confuseconfuse

Haha I'll edit it, just for you...

Jarrah


 

Did I ask myself why the diaphragm jet was also called the pilot? confuse it's not a good morning!



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AP. To check the accelerator pump is working properly- Remove carb from bike and fill with fuel to check if the carb squirts fuel when the throttle is applied. You should see a nice stream of fuel. If not, repair AP.

 

So you have a better understanding of the diaphragm/fuel pump

The accelerator pump squirts fuel into the carburettor when the throttle is opened from just before half throttle through to just before full throttle . This prevents it getting lean when the throttle is applied all of a sudden & hence enhances the response.When the diaphragm is pushed down by the diaphragm lever arm (top of carb with a spring under it) sucks fuel from the one-way valve & pushes it up to the check valve. This is where you can check the other one-way valve & diaphragm by pushing down GENTLY on the diaphragm while the bowl is full of fuel. It should squirt the check valve out if it's not held down by the gasket so BE CAREFUL! Remember eyes aren't made to have fuel in them

Posted Image

 

 

 

It then goes up to the diaphragm/fuel pump nozzle.

Have a look from the other side (not the side shown in the pic below), there will be a small hole. Use a piece of fine wire to unblock it and also use carb cleaner or fuel. If you have trouble finding fine enough wire- cut an old cable (throttle, pushbike cable etc..). Compressed air also helps. It may take awhile poking and prodding but you will get it clean. I used a pair of long nose pliers to assist in holding the wire and prodding.
406295_542053209161488_1860940543_n.jpg

 

Once you have the carb together connect the fuel line to the carb & check that you have a nice stream of fuel squirting out the accelerator pump nozzle when the throttle is applied (obviously manually). Again... Remember- eyes aren't made to have fuel in them!

Enjoy!

Jarrah



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Better smile



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yamaha42 wrote:

Better smile


 Thanks for letting me know lol, I took it from my ''rough'' info that I store online. smile

Enjoy!

Jarrah



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