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Post by scottkooi on May 14, 2011 16:14:50 GMT -5
Hey guys- I am experiencing an issue with my 02 eton beamer. To begin, I will tell you what I have had done to it- 70cc bb kit hp carb new intake hp choke hp fan kit technigas pipe, installed rollers that came with pipe(unk weight) removed oiler-premix at 32:1 ratio stock air filter unrestricted rpms The issue that I am experiencing is that at 37 mph(per gps) it makes a "crackling noise" from the exhaust. At this point it feels as though I am at wot, however, I am afraid to open it up anymore when the noise starts because my mech. has blown it up twice already. It sounds like a dirt bike with the pipe I have on it, but this is more crackle than normal. I also feel that I should be getting more speed in relation to the rpms that the bike is pushing(again, no tach, so I am going by what it sounds like). These are pics of the plug at 100 miles.    |
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Bong
Scoot Enthusiast
Posts: 235
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Post by Bong on May 14, 2011 16:35:02 GMT -5
:welcome: Whats up Scott. Now lets figure this out. I am learning too. Like I said this is the place for 2 smoker info. Good bunch of guys here and I hope I was not wrong. |
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Post by reveeen on May 14, 2011 17:17:50 GMT -5
Any ideas on the compression (in PSI)?
And if that plug is a #6 you should be running an #8.
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Post by scottkooi on May 14, 2011 17:35:51 GMT -5
I have no idea what the compression is- I haven't asked the mech that did the bb kit for me. The plug is a BPR6HS NGK R. Will the 8 burn hotter?
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Post by reveeen on May 14, 2011 17:44:47 GMT -5
Colder........... it sounds like you are pre-igniting. (one of the two conditions that affect exhaust sound)
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Post by scottkooi on May 14, 2011 17:49:00 GMT -5
I have a 7 on hand. Would this affect how high the rpms seem to be? If I understand you correctly, this may be the reason that I'm getting the crackling noise close to wot. Not sure if that would result in such a low top end speed?
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Post by reveeen on May 14, 2011 18:03:05 GMT -5
If the engine is "pre-igniting" it is firing early before the piston reaches top dead center. This is a hard thing to understand, because all engines fire the plug before top dead center, but it takes time for the mixture in the cylinder to ignite, so typically the plug firing is advanced, so that the mixture is lit and burned "on time". Too early and ignition causes resistance, too late and maximum benefit is not achieved.
When you "build" an engine you set the "squish" (or compression), this is why I asked you for a PSI number.
When you build one of these 2 strokes you run the coolest plug, BPR8HS, and tune to that plug.
Both, too much compression, and too hot a plug, will cause pre-ignition in a 2 cycle motor.
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Post by scottkooi on May 14, 2011 18:12:14 GMT -5
I appreciate your help and input reveeen. Is preignition going to cause high rpms and low speed? If I put an 8 in it, what can I expect and what will I have to do to it? I also appreciate your understanding as well, I really don't have alot of knowledge which is the main reason that I had someone else do the mod for me- however, I am less than pleased with the result and I would rather not have to take it back to him.
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Post by reveeen on May 14, 2011 18:13:57 GMT -5
When you install a BBK you would typically be checking your front pulley for black marks. The black marks indicate belt slippage. Most folks automatically put a stronger spring in the take-up (rear) pulley to increase tension on the belt to counteract this tendency to slip. Of course this means that the weights you have in the front need to be swapped for heavier ones to counteract this extra belt pressure.
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Post by scottkooi on May 14, 2011 18:22:21 GMT -5
To be honest, I don't think that he did anything to the cvt-I know he would've charged me for it if he did! I have not taken the cvt cover off yet to look at any of it. I think it would be safe to say that the rollers that came with the pipe are the ones that are still in the variator, I put them in there. I am nervous about really technical issues and my wife is even more nervous about me touching those areas, ha ha ha.
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Post by reveeen on May 14, 2011 18:40:29 GMT -5
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Post by scottkooi on May 14, 2011 18:48:39 GMT -5
I don't have a problem digging into the cvt. I was actually considering getting an hp clutch and bell from partsforscooters, along with new springs. I suppose I should add a bit of history at this point- the mech. had my scoot for a few days shy of a year, he blew the original bb kit up twice and opted for a cast bb kit which puts me where I'm at now. Like I say, I definitely should be getting more speed for the rpms that I'm running. 37mph is way too slow for 1100.00!
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Post by reveeen on May 14, 2011 19:08:51 GMT -5
For the most part cast iron cylinders won't make enough power to require a specialty clutch and bell. When your clutch wears out (and it will) buy a quality Ferodo clutch.
I *think* if you can get your pre-ignition under control (the plug may do it) and maybe a #1000 contra spring, a gram heavier (each) on the weights (rollers), and maybe 2000 rpm clutch springs you should be happy with the results.
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Post by scottkooi on May 14, 2011 19:20:34 GMT -5
Well, that sounds like a relatively inexpensive place to start. I hate to just throw money at this, but I hate to take it back to the mech. even more! I'll order the parts and see what that does for me. My idea is that I should be able to run close to 60mph with this thing, is that unreasonable?
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Post by reveeen on May 14, 2011 19:30:14 GMT -5
You may have to up gear, 50-55 is not unreasonable, but 60 is reaching. I just broke 50 on my 50cc Zuma, and on a good day I weigh 250 @6'6".
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