Posted December 21, 201410 yr Ok bike starts lovely now first or second kick and ticks over great...she will appear to rev OK stationary but when you ride her she sounds and feels like she has run out of fuel and just about to burst into life but doesn't do so....so you get this hesitation/bogging at 1/2 throttle and above. Cannot say I have ridden her far as she has no insurance,tax or MOT just up our road a couple of times but she seems poorly .....carb is spotless and I'm out of idea's as what else to try....main jet wrong ?...didn't see any numbers on it when it was last out...well non were obvious ...
December 21, 201410 yr Aye XR" an engine will rev freely in neutral, as it needs only a whiff of fuel. sounds like your float levels low, it wont be the main jet, as you need to be wide open to bring that into play,,,needle jet or lift needle two notches,,, Take off fuel pipe from tank, open cock, and see the flow,,also
December 22, 201410 yr Author Aye XR" an engine will rev freely in neutral, as it needs only a whiff of fuel. sounds like your float levels low, it wont be the main jet, as you need to be wide open to bring that into play,,,needle jet or lift needle two notches,,, Take off fuel pipe from tank, open cock, and see the flow,,also Hi Blackhat, thanks for info, float height is spot on and fuel runs freely from tap, I have an inline filter fitted and there is plenty of fuel in there....I have removed pipe from carb and opened tap to confirm it's running well. The bike hasn't been ridden for 21 years of course she has fresh petrol and a carb rebuild etc but would being standing for long period cause the bogging down ? the book says 3rd notch for the clip position would it be worth trying another groove ?
December 22, 201410 yr Moderator Have you actually had the engine up to proper operating temps. 2strokes are really bad from cold esp if there is a lot of oil and fuel sloshing around from a lot of bad starting. One tip that can help. Warm the head with a heatgun. Till its too hot to touch. Same with the plug (blowlamp for that one). Get the plug in as fast (carefully) as you can and try and start it. The warm head and hot plug will make the fuel oil mix ignite a lot easier.
December 22, 201410 yr Author Not having a 2 stroke since 1981...MT5 I'm a novice as to how to see if they are running at temp etc,...here is a video of it running.... https://www.youtube.com/watch?v=_ZruYZwGzmo How long would it normally take to warm up ?
December 22, 201410 yr Think its just cold..maybe you need to ride it further to make sure its warmed up..then wring its neck..my RD runs like crap quite awhile until its warmed up..although my DT`s warm up much quicker. Also when you cleaned carb did you make sure pilot circuit is 100% clean (ie:pilot jet and orifices in the carb)?
December 22, 201410 yr Author Think I need a long private road....lol....wasn't planning on using the bike till the sun shines....March onwards as such she don't have any MOT, TAX or Insurance....might get the bike rack out and take her somewhere private for a blast ...
December 22, 201410 yr Listening to Video" she sounds choked. is the airfilter oil coated,, clean it , and lightly oil , screw air screw out a half turn,
December 23, 201410 yr Author Brand new Yamaha air filter it came pre-oiled, airscrew 1~1/2 turns out as per book .....
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