tom675 Posted December 28, 2015 Report Share Posted December 28, 2015 I have a new 2016 evo 300 2t. Bike runs a little rough off initial throttle, id say first 3rd of rev range. Iv tried adjusting air screw, moving needle clip, couldnt improve, so back to factory settings for now. Has anyone cured this problem, a few riders iv spoke to seem to have same issue Quote Link to comment Share on other sites More sharing options...
worldtrialchamp Posted December 28, 2015 Report Share Posted December 28, 2015 I've found the fuel metering in the idle circuit is deliberately a little rich. But all the Betas I've had have been this way...I also experimented with this and also went back to the factory setting. getting used to that now Quote Link to comment Share on other sites More sharing options...
steve_earle Posted December 29, 2015 Report Share Posted December 29, 2015 Check your float level and while you are there check what jets it's running. Also give the carb a good clean, As it's new it doesn't mean its clean as the carb was probably pulled from a box and just chucked straight on the assembly line. The Beta's are shipped with a rich pilot, (52 I think from memory) a 48 or even a 45 does clean them up off the bottom, But that's a last resort as it should run o.k and work as intended from new. Jetting is personal preference. If after checking the float height and cleaning it does not solve it, Take it back to the dealer and ask them to pdi it properly. Quote Link to comment Share on other sites More sharing options...
dan williams Posted December 30, 2015 Report Share Posted December 30, 2015 The Keihin carbs are notorious for getting water bubbles or dirt flecks in the exit hole of the pilot circuit just behind the slide at the bottom of the bore. The actual hole is tiny. You have to disassemble the carb and blow it out with compressed air. I usually have to do it two or three times a year. You can take the tower off with a T20 torx security bit. Be very careful not to damage the little O-ring type gasket on the front face. Quote Link to comment Share on other sites More sharing options...
worldtrialchamp Posted December 30, 2015 Report Share Posted December 30, 2015 the spark plug requires cleaning at the first service interval..might be dirty Quote Link to comment Share on other sites More sharing options...
tom675 Posted December 31, 2015 Author Report Share Posted December 31, 2015 Thanks everyone. Had the bike since October and ridden every week.done first service already. Cleaned carb out numerous times and still no better. Tried adjusting air screw which made minimal difference, lifted needle clip to middle position which made it worse, so back to standard settings on carb.it comes with a 48 pilot so iv got a 45 to try in it. Really frustrating as rest of bike is lovely Quote Link to comment Share on other sites More sharing options...
benbeta23 Posted December 31, 2015 Report Share Posted December 31, 2015 Try a BPR5ES plug rather than standard 7, Engine runs cleaner, It may help improve it. 1 Quote Link to comment Share on other sites More sharing options...
slicktop Posted January 1, 2016 Report Share Posted January 1, 2016 (edited) I run an Iridium plug and avgas and race mix on a 13 evo. I'm a big proponent of smart carbs, but the stock Kehien has been flawless so I can't justify buying any thing new. Clean the carb real good and run non ethanol fuel. Edited January 1, 2016 by slicktop Quote Link to comment Share on other sites More sharing options...
tom675 Posted January 1, 2016 Author Report Share Posted January 1, 2016 I have tried a bp5es plug as recommended by local riders, but it made little difference, and felt it rsn slightly cleaner on a bp7es. I havnt tried an iridium plug yet but have on previous bikes and thought very little change. Going to take carb apart AGAIN and see if i can spot anything amiss whilst fitting a 45 pilot Quote Link to comment Share on other sites More sharing options...
redhubuk Posted January 1, 2016 Report Share Posted January 1, 2016 Hi tom675, you didn't say if it had run ok when you bought it or it's developed this problem? Quote Link to comment Share on other sites More sharing options...
tom675 Posted January 1, 2016 Author Report Share Posted January 1, 2016 I dont remember an issue first ever time riding it but that could of been down to excitment haha definitely been an issue since, so id guess its always been there, although it does appear to be getting worse. Other riders have had a go and agree its not right Quote Link to comment Share on other sites More sharing options...
redhubuk Posted January 2, 2016 Report Share Posted January 2, 2016 Does it do it in both Map settings as mine is rough of the bottom in Dry setting, didn't help that Beta changed the colour of the switches over for lights and map and didn't update the manual. Keep an eye on the exhaust muffler to plastic end piece joint, is there any smoke coming out there?, as mine had badly assembled exhaust packing and was blowing. When I took the end cap off I could see most of the exhaust wadding had caught on a internal screw boss, and scrunched all the wading up to one end, so it wasn't silencing properly and getting really hot. Just re-assemble the pipe with packing but take time to pass it by the screw boss. Oh and make sure you pop the flywheel cover after every wet ride or jet wash as the new waterproof cover.... isn't. No need to remove, just 2mm gap will do, leave until next ride to dry out. Not sure if these help your problem but just some tips if not. Quote Link to comment Share on other sites More sharing options...
steve_earle Posted January 3, 2016 Report Share Posted January 3, 2016 When you take the carb apart remove the jet tower that's held in place with 2 tamper proof torx screws. There is a rubber gasket in there and one side is glued to the jet tower. I have seen one with excess glue that was blocking one of the passages. Quote Link to comment Share on other sites More sharing options...
redhubuk Posted January 4, 2016 Report Share Posted January 4, 2016 When you take the carb apart remove the jet tower that's held in place with 2 tamper proof torx screws. There is a rubber gasket in there and one side is glued to the jet tower. I have seen one with excess glue that was blocking one of the passages. Had these images to hand, I think it shows what steve_earle recommends. Quote Link to comment Share on other sites More sharing options...
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