Motorized Bicycle Engine Kit Forum  


Go Back   Motorized Bicycle Engine Kit Forum > Motorized Bicycle > Motorized Bicycle General Discussion

Motorized Bicycle General Discussion All topics regarding bicycles with engines.

Thread Tools Display Modes
Old 10-13-2014, 08:09 PM
Davezilla's Avatar
Davezilla Davezilla is offline
Motorized Bicycle Elite Member
Join Date: Mar 2014
Location: San Antonio Texas
Posts: 2,710
Default Re: Newbie questions for upgrading

I agree on the jet size issue... these jets aren't drilled very accurately so investing in a set of small gauge drill bits, a pin vise, and even a set of jet gauge pins to verify the size of unknown jets or if you have several jets drilled and need to know which one is which...
Definitely let the engine break in before trying to tune it as it won't behave the same or make full power until after at least 3 tanks of fuel.
Reply With Quote
Old 10-14-2014, 12:11 AM
UTmotorbiker UTmotorbiker is offline
Motorized Bicycle Newbie
Join Date: Oct 2014
Location: Utah
Posts: 16
Default Re: Newbie questions for upgrading

Ok, that sounds great. My engine only has about 55 miles on it so far but I should have it broken in in the next week or two. I will refrain from trying any mods except the 41T sprocket until that happens but I definitely think cruisin at 30 mph will suit my needs quite well. I only use it to commute from school and work and back, both of which are under 3 miles away.

Okay, so one last question... what do you all mean when you say it's "four stroking?" I have been trying to figure out what that means and how to diagnose it on my engine but I honestly have no clue what it means when you say that. Can you give me some easy to understand language that describes that? I am definitely a newbie when it comes to 2 stroke engines and fairly new to the motorsports in general (although I have ridden 2 and 4 stroke dirt bikes before, but not for some time).

Thanks guys!
Reply With Quote
Old 10-14-2014, 02:29 AM
nelsonk1969 nelsonk1969 is offline
Motorized Bicycle Senior Member
Join Date: Sep 2014
Location: Lake Worth Florida 33467
Posts: 63
Default Re: Newbie questions for upgrading

Hi 4 stroking is a term used when a Two stroke engine runs poorly and fails to fire the air fuel mixture consistently.
if you keep your mods well planned your engine tuned and decarbonized you will not likely encounter this problem.
color tuning is a way to insure your Air fuel mixture is set correctly
I have used this kit many times on motorcycles I am not sure if they have the size that will work on your Two stroke motor.

You can also go old school and simply read the spark plug as it a good indicator of your current tune.

and never take for granted that all the basics are good as a slightly dirty air filter can starve the motor of air making the engine run rich.
if you have a dirty air filter you don't want to cure it by filling in your jets and drilling them out smaller. same goes with the fuel filter if you have one and you do have one right?
if the fuel filter clogs up and starves the motor of fuel this is no reason to drill the jets bigger.
Keep it simple and make sure the bike is at its peak before you start to modify it as many poorly planed engine,exhaust and or carb mods will leave you with feeling that you were better off when it was stock.
Reply With Quote
Old 10-14-2014, 05:06 AM
Greg58's Avatar
Greg58 Greg58 is offline
Motorized Bicycle Elite Member
Join Date: May 2011
Location: Newnan,Georgia U.S.A.
Posts: 2,620
Default Re: Newbie questions for upgrading

When a two cycle engine four strokes the engine sound changes sometimes, kinda like a flutter or a lawn mower. The bike I ride most four strokes a little till it warms completely, you can hear mine four stroking in the first part of my video of the red oak covered bridge ride part 2.
Your results may not be the same,Greg
Reply With Quote
Old 10-14-2014, 09:46 PM
Henshooter's Avatar
Henshooter Henshooter is offline
Motorized Bicycle Elite Member
Join Date: Feb 2014
Location: Melbourne au
Posts: 278
Default Re: Newbie questions for upgrading

I heard a good explanation of four stroking ,it's not 100% accurate but non the less fairly close to the description , that is China girl four stroking sounds like a Harley with a 5000 lb elephant on it ,yes it's loud and it pops but it just ain't going nowhere ,a good chinagirl that doesn't fourstroke sounds like a sweet symphony of explosions ,something like a shot of good whiskey ,smooth right the way through with a good kick at the top end
Light travels faster than sound ,ergo some may appear smart until you hear them speak
Reply With Quote
Old 10-17-2014, 10:23 AM
steveanson steveanson is offline
Motorized Bicycle Newbie
Join Date: Oct 2014
Location: Houston, TX
Posts: 10
Default Re: Newbie questions for upgrading

Originally Posted by UTmotorbiker View Post
Hey guys, thanks for the info. I have been doing a fair amount of research and I have heard a lot of what you guys have been saying. I live in a pretty hilly area but I'm hoping that the 41T will still let me climb the hills and give me the boost in mph I'm looking for. I kinda get the sense its running a little rich and guzzling gas a little more than it should be. Any recommendations?

My bike runs sluggish when its cold but then picks up speed after warming up. However I don't feel like it ever revs up that high and I'm hoping there is some little tuning things I can do to help it run a little better.

Thanks for the info guys!
My suggestion would be to learn to read your spark plug after your breakin. I don't have extensive experience with these little two strokes, but have tuned racing go-kart engines for many years. Your plug can tell many tales about what's going on concerning combustion...Steve
Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

All times are GMT -5. The time now is 01:22 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2016, vBulletin Solutions, Inc.