beta bodger Posted March 31, 2007 Report Share Posted March 31, 2007 Ive just added some boyeson reeds to my bike and WOW! What a difference! the bike starts runs and pulls so much better. Anyway back to the point. I checked the colour of the plug before i started so that i could tell if the bike was running any richer. The plug was black and looked very oily before I added the reeds and after I fitted the reeds, the plug is still the same colour. I am checking the plug by running the bike for say 10 mins and then killing the engine. I am not reving the engine but simply letting it idle. Is this the right method to check the plug? The plug that I am using is the one that came with the bike which is a NGK B7ES. The plug looks in good condition. I note that the standard should be a NGK BP7ES. So I am wondering is the fouling of the plug down to the model? Or should i change something on the carb??? Quote Link to comment Share on other sites More sharing options...
ask greeves Posted March 31, 2007 Report Share Posted March 31, 2007 (edited) Ticking over will prove nothing, your on the idle jet. Secondly using the same plug will not give an accurate reading, as the plug has been coloured , as the mixture was before. Although if the mixture now is say 'alot weaker' the plug would still turn maybe a little greyish. I personally would give it a real test, loadsa big hills , flat out in 4th touch, see how it really performs, then kill the motor, don't let it tick over, as that'll distort the reading, then check the plug. DISCLAIMER...if it blows up , flat out in 4th, it's tough... at the top ! Edited March 31, 2007 by ask greeves Quote Link to comment Share on other sites More sharing options...
the addict Posted March 31, 2007 Report Share Posted March 31, 2007 (edited) Ask Greeves is right, I do plug chops after 8-10 real big flat out climbs, kill the engine imediatley you hit the top of the hill and take the plug out. It wont work if you tickle back to the van to take it out. I did nt need to rejet mine after putting the Boyesens in at all, infact it sorted the plug fowling out on its own. Always worth checking the plug colour after a good days trial or practice to see how its been running that day. Plug should be light brown and pretty much dry, oily and black isnt the right colour at all. If the plug is white or pitted its too weak, richen the mix straightaway on main and pilot and try again. Chuck the 7Es in the nearest bin and get a BPR5ES as recommended by Lampkins for the UK, it will make a difference straightaway and the Champion plugs are ***** in Betas Edited March 31, 2007 by Betarev3 Quote Link to comment Share on other sites More sharing options...
lee harris Posted April 1, 2007 Report Share Posted April 1, 2007 (edited) Changing the reeds will not change the mixture in any way. if it woz gud before, it will be with the new reeds. New reeds may give more power which means more air fuel mix is is getting into the combustion chamber. The pre-mixing as itr were is done upstream IUf the airfilterm size, inlet tract etc etc is the same nowt will have changed. A plug chop, ie full gas in forth will only tell you if the main jet is correct. Dont gas it and roll to a stop. Hit the kill switch and clutch at the same time on a long road wide open throttle uphill, say 60 seconds long. Coast to a stop. If the plug is grey you need a bigger main jet, if its white you will melt a piston on WIDE OPEN THROTTLE: In reality, no trials bike is driven on WOT for more than a few seconds, thats why we dont mlt piston often OR, if you drop the bike for say 30 seconds on WOT, it WILL die. The pilot jet and needle are what you need to worry about but this can only be done subjectivly assuming you have no rolling road. If you just change the reeds , dont mess with it!!! Lee Edited April 1, 2007 by Lee Harris Quote Link to comment Share on other sites More sharing options...
motojojo Posted April 1, 2007 Report Share Posted April 1, 2007 Before you do anything I would check that plug, I run 5s not 7s, but I ride a Gasser not a Beta. Find out what other beta boys are running. A cold plug wont run very hot. If the bike runs good, just change plugs more often, or lower your needle jet. Just make small changes and only one at a time. Is your air screw or fuel mixture adjusted right? Less fuel or more air makes a big difference. If your adjustment screw is in front of the slide (closest to the air filter) its air and if its after the slide its fuel. In order to adjust, screw in the idle alittle bit then screw in the adjustment screw, then unscrew it half a turn then rev your throttle open then off real quick, do this till your idle goes up then down with out alot of popping, smooth up then smooth down. Quote Link to comment Share on other sites More sharing options...
beta bodger Posted April 10, 2007 Author Report Share Posted April 10, 2007 I had the bike out this weekend and it seemed to be runing a bit rich. Plug was oily black when doing a plug check as described above (i.e flat out in high gear). I killed the bike to have a rest then I could not re start it. tail between my legs i drove home and sweared a bit. decided to swap the plug and it started first kick. Conclusion it must be running rich but the air screw is only 1 - 1 1/4 turns out! Quote Link to comment Share on other sites More sharing options...
ssiegmund Posted April 11, 2007 Report Share Posted April 11, 2007 I had the bike out this weekend and it seemed to be runing a bit rich. Plug was oily black when doing a plug check as described above (i.e flat out in high gear). I killed the bike to have a rest then I could not re start it. tail between my legs i drove home and sweared a bit. decided to swap the plug and it started first kick. Conclusion it must be running rich but the air screw is only 1 - 1 1/4 turns out! 1.25 to 2.5 is an acceptable range for the air screw. 1.25 is rich in my opinion. My '06 Rev3 250 is running 27.5 pilot, 145 main, needle 2nd from the top, air screw 2.0, at 440' above sea level N44 02.834 W123 01.170. This works well for 1st and 2nd gear riding. Quote Link to comment Share on other sites More sharing options...
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