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Hello from Brighton
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Recently bought a 2003 blue TTR off a forum member who has hung his boots up. I think he was sad to see the bike go but I am happy to give it a new home.

The romance period was pretty short, however, as after the first ride I noticed that the bike was idling-high, i.e: not returning to a low idle after being warmed up and ridden normally.

The bike idles normally when turned on cold and will momentarily idle normally if killed hot and started, but then it appears to idle high again.

The previous owner mentioned the last use was in February (for the MOT) and advised me to fill the tank up before first ride (which I did). I believe him to be a stand-up chap and he said that he had had no problems like the one I'm having previously, so my current theory is potentially bad fuel has done something to the carb?

My plan of attack is as follows:

1) check the carb mix screw - apparently hanging idle can be due to the mixture being lean (although what I've read suggests it should still return to normal idle after a short period and mine doesn't) (this video seems like reasonable advice for someone who has never done this before? https://www.youtube.com/watch?v=zm5mB3R8Ucw )

2) on the way to work put some fuel additive from the motorbike shop into the tank and see if that does anything - try and put 10-20 miles on it a day for the next few days or until the fuel runs out

if neither of these two solve the problem then:

3) check where the rubber meets the carb for leaks on the inlet stub (is there a good method for doing this?)

4) buy a carb rebuild kit and rebuild the carb based on the excellent tutorial on ttr250.com

Any advice appreciated.

I'm hoping to mod the bike a bit so looking forward to taking some pics and doing some write ups to post on the forum.

Cheers,

Rob

p.s. if anyones around Sussex ways and fancies going for a ride feel free to shoot me a message

 

 



-- Edited by robs on Wednesday 30th of May 2018 10:21:27 PM

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Welcome to the forum, Robs.

I hope you've not bought a bikeof trouble and can resolve the problem easily.

I agree with your diagnosis regarding fuel.
I'd advise emptying the tank and putting fresh in - using the old petrol for cleaning instead.

Others will be along to offer their help for sure. wink

Martyn



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Budleigh Salterton. Devon



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How high do you think it idles when it's hot? My bike idles a little bit higher when hot but I think that's normal for carbed bikes.

 

This guy seems to be having similar issues: http://ttr250.activeboard.com/t64633728/high-idle-when-riding/

Is your header pipe getting very hot aswell?



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I would take the carb off and inspect the inlet stub thoroughly, easy thing to start with and if it has been standing for a while it could have perished or become un-bonded from the metal part. 

Edit, spelling again!



-- Edited by ttr steve on Wednesday 30th of May 2018 10:17:49 PM

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totallyttrs.com

 



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Cubber: I'm sure it is fixable! You're right about fresh fuel, I'll try fresh fuel and additive..

 

Ether: I think it's more than idling just a little bit high, maybe I'll try to take a video? Thanks for the link, I'm not sure if the header pipe is glowing hot but I'll definitely check.

 

Steve: I'll try this first then, the more I read the more it sounds like this is the most likely cause..

 

Thunderstorms in Brighton today so I'll either do this if they clear up or it'll have to wait until tomorrow.

 

Thanks for advice so far.

 



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This video shows:

1) the bike immediately after switching it on, first idling high due to choke until its warmed up

2) choke off at 30 seconds, still idling high initially and then some variation takes place

3) 1:05 - bike settles down and starts idling normally

4) 1:35 - kill and restart the bike and bike idles normally

5) 1:40 - rev the bike, takes 10 seconds until bike returns to normal idle

6) 1:50 - rev the bike higher (phone compensates for volume and lowers it) takes 10 seconds to return to normal idle speed



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This video shows the bike idling high after a 5 minute ride around the block, I wouldn't usually leave it running like this but I wanted to show how no matter how long you leave it for it doesn't return to a normal idle.

At around the 40 second mark I killed the bike and restarted it and you can hear it idle normal for just a second before ramping up again.

Hope this helps explain the problem I've been seeing in better detail.

Tomorrow I'll try the various things discussed previously and report back.

Cheers,



-- Edited by robs on Thursday 31st of May 2018 06:35:56 PM

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After all that I think I've managed to fix it by adjusting the throttle cable tensioner and air/fuel mix screw.

And just for good measure I doused the rubber inlet boot with wd40 and didn't detect any change in idle speed.

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Well, it's a start and an improvement.

I do hope it's completely better and not one of the recurring carburettor problems type that TTRs seem well versed in.

Good luck, the proof will be seen in time. wink

Martyn



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Budleigh Salterton. Devon

z1g


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Hi,
This is exactly like my bike mention in posts above.
The difference with my bike was when choke is turned off, it goes back to normal almost instantly??
But i can relate, as after riding, whilst riding it was revving hard. Possibily less than yours. But still to high for my liking.

PLEASE KNOW I AM NEW AND NOT QUALIFIED REALLY TO OFFER ADVICE.

For me. What seems to have worked regarding high rev was, i tightened the throttle cables, and fully unscrewed the idle screw all the way, then about two turns in.

I am still having problems myself with high temps, and have been offered some really good advice in my thread.
Which i will be doing asap.
Z.

edit:added link again (skip to bottom for the good advice aka ignore mine)

http://ttr250.activeboard.com/t64633728/high-idle-when-riding/

 



-- Edited by z1g on Monday 11th of June 2018 10:24:39 AM

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