Stock motor 38MPH

DRK

Member
Apr 1, 2017
90
14
8
Illinois
This bike runs great all the way from 0mph - 38mph, no 4 stroking, no hesitation, pulls hard. I believe I'm getting everything out of this motor that it has. The problem is it will only do it without the air filter. Even using just one layer of panty hose with a rubber band for an air filter it drops 5 mph and 4 strokes. My question is, is there anyway I can get 38 mph and run a GOOD air filter? If you need anymore information just ask. Thanks.
 
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crassius

Well-Known Member
Sep 30, 2012
4,032
156
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USA
one might try a larger filter opening with a 'still air box', but that would require a lot of ducting
 
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DRK

Member
Apr 1, 2017
90
14
8
Illinois
Thanks Crassius. Sadly, that's probably the correct solution. I just don't see me running duct work to a air filter the size of a dinner plate. lol! Thanks again.
 
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DRK

Member
Apr 1, 2017
90
14
8
Illinois
I sounds like one jet size smaller will be perfect with a air filter. (^)
Might try that. I'm running a Speed carb now with 66 jet, c-clip full rich & a 4'' long exhaust. Got 40mph going both directions on level blacktop. I realize this isn't good for my motor. Just want to find out how much can be gotten out of a stock motor without spending money on it. But I did have to buy a complete set of jets. I would like to be able to hit 40mph with a Good air filter & a semi quiet exhaust. I doubt I will be able to realize my goal. But hey, never hurts to try! Thanks for the advice VMB!
 

Slogger

Member
Sep 8, 2014
545
4
18
nohio
Hey Slogger, if I ran a air filter & exhaust that's probably as fast as mine would run.
I generally ride around at about 24, 25 mph anyway. My brakes and stuff are lame and I'm not in a hurry. The muffler is worth a few mph.
to me.
 

DRK

Member
Apr 1, 2017
90
14
8
Illinois
I generally ride around at about 24, 25 mph anyway. My brakes and stuff are lame and I'm not in a hurry. The muffler is worth a few mph.
to me.
Yeah. 25mph is about where I cruise at most of the time. This is my first 2 smoker, just tryin' to find out what I can get out of a stock motor.
 

mobike91

Member
Sep 14, 2010
111
2
18
lebanon, oregon
38 out of a completely stock setup is pretty good. I wouldn't worry about the max speed. I'd worry more about max longevity. Iv had a few kits only last 100 miles before seizing up lol. Back when I was 16 and loved hitting wide open without a idle screw haha. It ran lean....
 

DRK

Member
Apr 1, 2017
90
14
8
Illinois
That's definitely a possibility! I'm 61 years old, but when I get on this thing, I feel like that numbers' reversed. You have a great by-line Mobike91..wee.
 

mobike91

Member
Sep 14, 2010
111
2
18
lebanon, oregon
After about the 15th engine destroying itself in another various way, I began to realize that these little engines were not meant to be primary transportation and a racecar lol. One must have both a put put bike and a experimental race bike to be satisfied in riding these. My favorite engine detonation was when A roller bearing broke and tossed bearings into the cylinder, Swiss cheesing both the head and piston but some how it kept running at much less power. I rode that engine out for another 80 miles before a piston ring broke and scarred the cylinder, but man it was a die hard lol. zpt
 

Motakitty

Member
Feb 14, 2015
447
3
18
San Jose, ca
I had the same issue. My stock air filter fell off and it felt like it had a turbo so I knew it needed a better flowing filter. I ended up modding a foam uni foam filter from a Honda ruckus and it runs just like it did without a filter
 

DRK

Member
Apr 1, 2017
90
14
8
Illinois
I had the same issue. My stock air filter fell off and it felt like it had a turbo so I knew it needed a better flowing filter. I ended up modding a foam uni foam filter from a Honda ruckus and it runs just like it did without a filter
Thanks for the info on the Uni filter. Was wondering if one of those would flow enough air.
 

Greg58

Well-Known Member
May 1, 2011
4,186
1,064
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Newnan,Georgia U.S.A.
As Norm said jet down and it should run correct with the air filter, be sure and keep an eye on the spark plug color to keep from going too lean. lean makes heat, heat melts parts, engines seize, rear tire locks up, wait I may be telling too much. Don't ask how i know!