A forum for owners of Yamaha TTR250 trail and enduro bikes!

Members Login
Post Info TOPIC: Poor running at higher rpm


Member

Status: Offline
Posts: 11
Date:
Poor running at higher rpm
Permalink  
 


Hi 

My name is Ross Mckinlay I live in Essex and have a 2004 Blue TTR. I have just joined the Forum and am after some advice!

One of the reasons i bought the TTR was so that i could learn to do all the maintenance myself as Im not that confident/experienced

I was trail riding on Sunday and the bike started running roughly in the 2nd half of the rev range from about 50mph onwards it tops out at 70.

I hasten to add that it wasnt a problem on the trails only on the roads in between!

I suspected dirt in the carb as eventually it cleared itself and for the last two hrs was running fine.

I would like to take the carb off and have a look. I have had a look at the bit on cleaning the carb on the forum which is very helpful but am unsure as too whether this is necessary now or if i do take the carb off where is the problem likely to be?

If anyone has any advice it would be appreciated

Thanks Ross

 

 

 

 

 



Attachments
__________________


Super Guru

Status: Offline
Posts: 1808
Date:
Permalink  
 

I would check your fuel for water, drain a little from the drain screw, check your air filter and check the inlet stub, before you take the carb apart. But it does sound like a blocked jet.



__________________

totallyttrs.com

 



Super Guru

Status: Offline
Posts: 7315
Date:
Permalink  
 

Welcome to the forum Ross!

The fact that your TTR runs out of steam at the top of the rev range does point to a fuelling issue.

As Steve suggests, drop some fuel out by loosening the drain screw at the bottom of the carb float bowl. Be very careful when doing this that you have a really good fitting screwdriver and try and hold the carb so that you can put some pressure on the screwdriver as these suckers can be tight and have been known to round out  cry

Try and catch what comes out to check how clean (or not) the fuel is. Also let the fuel run out for a while to check that you have a good flow of fuel from the tank as, if any of the filters are partially blocked, the fuel won't be getting into the carb fast enough to sustain higher revs.

Don't smoke or light a match whilst doing this evileyedohbleh

A less common fault that shows your symptoms is a blocked vent on the tank cap. If enough air can't get it a vacuum can be created in the tank and slow the flow of fuel.

Brian



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Member

Status: Offline
Posts: 11
Date:
Permalink  
 

Hi

Thanks for the replies the time before last i was a little over enthusiastic going through puddles which did cause a misfire which cut the bike out until i sprayed the plug with WD40.

This did feel different as it was in the 50 - 60mph area it would stutter its way from 50 to 60mph in top and was always worse after a bumpy track!

It did eventually clear and was running fine at the end

I will have a look for where the drain screw is on the forum before i attempt anything!

Do i have to remove the carb?

Thank you both for your help

Ross


__________________


Member

Status: Offline
Posts: 11
Date:
Permalink  
 

Just had a look at my drain bolt and its mullered looks more like a torx head than a phillips but unfortunately it isnt!

Ross

__________________


Super Guru

Status: Offline
Posts: 1808
Date:
Permalink  
 

Oh Dear, good luck with that.

Just a side note, one of my bikes and a few other owners have a bit of a problem when going through water and we find that taking the drain pipe off the emulsifier and letting the watery oil crap out makes thing's work well. Still not sure how or why this works, but it does.

Hope it helps.

Steve



__________________

totallyttrs.com

 

Page 1 of 1  sorted by
 
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard