WR426 doesn't idle after throttle roll off
Posted January 03, 2009 - 02:34 PM
I'm the new owner of a used WR426. It's my first offroad bike. It looks like I get used with this bike and I observed the detail described below.
When I ride the bike in the first gear and I roll off (release) the throttle the engine doesn't idle but stays little higher even I roll off the throttle by hand. More than that, if I want to idle the engine I have to use the rear break.
Another scenario: I pull the clutch, roll off the throttle and the engine doesn't idle but it's a little bit higher. At this moment, if I release the clutch lever then the engine idle when the first gear is connected. Very important here, when I pull the clutch again, the engine idle.
First assumption is about throttle cable but I do roll off the throttle by hand, not just release it. In neutral I roll on the throttle 1/4 and release it immediately. Very rarely the engine idle after this action.
The second assumption is about the carburetor. Maybe a cleaning is required but the engine (+the carburetor) should be consistent and doesn't idle in above scenarios.
The third assumption is about TPS. I read on this forum about TPS mod and I disconnected it today for a while. It looked like the idle is better. I'll continue to experiment with TPS on/off. I cannot figure out how TPS can influence idle.
Please, can someone give me some suggestions or logical explanations?
Posted January 11, 2009 - 05:15 PM
Posted January 12, 2009 - 03:21 AM
TPS affects idle because it changes ignition timing. Check to make sure it is adjusted correctly.
Posted January 12, 2009 - 08:58 PM
Posted January 13, 2009 - 12:00 AM
Posted January 17, 2009 - 01:45 PM
Last time I tried the mod for airbox and I observed an improvement but still sometimes the idle is higher. The next step is to clean the carb and all jets. I'll check the TPS voltage too.
I never opened the carburetor and I don't know what jets I have. I'm thinking to buy a JD Jets Kit.