Motorized Bicycle Engine Kit Forum  

Sponsors



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

Motorized Bicycle General Discussion All topics regarding bicycles with engines.

Reply
 
Thread Tools Display Modes
  #741  
Old 04-28-2013, 10:25 AM
rustycase's Avatar
rustycase rustycase is offline
Gutter Rider
 
Join Date: May 2011
Location: Left coast
Posts: 2,745
Default Re: Motorized Bicycle Take a Tip...Leave a Tip

That's a great tip, Dave!

...I wonder if there will be any probs because it is not fuel/vapor rated???

Will you report back on how long it holds up for you?

if it breaks down, I wonder if it will send pieces of rubber into the cylinder??

tnx!
rc
__________________
My goal is cheap, reliable, personal transport, below the tax collector radar. Fun counts for a lot!
Reply With Quote
  #742  
Old 04-28-2013, 11:12 AM
SuperDave's Avatar
SuperDave SuperDave is offline
Motorized Bicycle Elite Member
 
Join Date: Sep 2011
Location: Panama City Beach, Fl. USA
Posts: 180
Default Re: Motorized Bicycle Take a Tip...Leave a Tip

It turned out it wasn't a leak from the carb/manifold (no discernible change, still ran lean & runaway idle when warmed up) but I've since replaced my crankcase seals under the magneto & clutch cover, it runs better now. They didn't leak oil or look bad, but I don't have a microscope to see if it was a micro-tear. Now I have to track down a short in my tail light. (Sometimes it works, sometimes it flickers or won't work at all). I don't wanna get hassled by "The Man" over something trivial.

It's been months since I tried the intake hose adaptation & so far so good. I did have to use a bit of grease to shove the intake into the carb "hose". It is a tight fit. If it has ingested any rubber, it hasn't 'complained' or given me problems. I did it last fall, but I haven't ridden it much since then, I wanted to fix the air leak before giving it much use, I don't wanna melt a piston. Money has been tight over the winter and what spare cash I've had on hand was spent on other things like bills, food, etc. Now that it's springtime & money is flowing a bit more, I'm back to getting my bike running decent.

Rusty, I understand your concern about the fuel vapor issue, seeing how the hose was not designed to carry fuel, but hot coolant. So far I have not had any problems with it, but then again, it's been maybe a dozen miles clocked on it since then, so I can't say definitively that it is goof-proof. If the gasoline does eat the rubber, it has to eat through a considerable amount before it can leak, seeing how tiny the original o-ring was compared to the length & thickness of hose I'm currently using now.

Remember, the primary ingredient of automotive coolant is ethylene glycol, which is a derivative of a long chain alcohol molecule. Consider again most times auto coolant is about 180 degrees Fahrenheit. If it can withstand all that, I feel confidant that the tiny amount of rubber exposed to gas vapors is minimal compared to what it was designed for.
__________________
By the holy power of Love, Life & Laughter, I commend you to Go Forth & Be Awesome!
Reply With Quote
  #743  
Old 04-29-2013, 11:35 AM
T_Raw T_Raw is offline
Motorized Bicycle Member
 
Join Date: Mar 2013
Location: Navarre, Florida
Posts: 21
Default Re: Motorized Bicycle Take a Tip...Leave a Tip

I rode the bike to work this morning. I haven't been able to check the carb. I wouldn't say it really bogs I guess it just has no pull after it hits about 15 mph. I used some gasket sealer on the o ring in the carb to try and seal the hole up maybe that will help and I will check the spark plug and post my findings when I get home
Reply With Quote
  #744  
Old 04-29-2013, 04:55 PM
T_Raw T_Raw is offline
Motorized Bicycle Member
 
Join Date: Mar 2013
Location: Navarre, Florida
Posts: 21
Default Re: Motorized Bicycle Take a Tip...Leave a Tip

Okay so I found the problem when I got the motor the bolts that run through the crankcase were not bottomed out so I fixed that. Runs better still not where it was when I first got it. Had it up to 31 the top speed now is 18. It's a grubee skyhawk 66cc engine stock with a CNS carburetor. I did mess with the air enrichment screw but would that cause me to lose that much speed? Any suggestions?
Reply With Quote
  #745  
Old 04-29-2013, 09:07 PM
crassius crassius is offline
Motorized Bicycle Elite Member
 
Join Date: Sep 2012
Location: USA
Posts: 3,017
Default Re: Motorized Bicycle Take a Tip...Leave a Tip

the bolts that run through the crankcase are important - don't miss the three that are under the clutch
Reply With Quote
  #746  
Old 04-29-2013, 10:22 PM
T_Raw T_Raw is offline
Motorized Bicycle Member
 
Join Date: Mar 2013
Location: Navarre, Florida
Posts: 21
Default Re: Motorized Bicycle Take a Tip...Leave a Tip

i did not check those but I will. bike ran just not well. I adjusted the float to try and get better rpms at a low speed because it runs better when the gas valve is shut off and now it wont start. lol.
Reply With Quote
  #747  
Old 04-29-2013, 10:53 PM
aussiedan aussiedan is offline
Motorized Bicycle Senior Member
 
Join Date: Feb 2013
Location: australia
Posts: 80
Default Re: Motorized Bicycle Take a Tip...Leave a Tip

Quote:
Originally Posted by T_Raw View Post
i did not check those but I will. bike ran just not well. I adjusted the float to try and get better rpms at a low speed because it runs better when the gas valve is shut off and now it wont start. lol.
sounds like you have a bad crank seal i had one bike that started to run bad and after replacing most gaskets,trying different carbs,exhausts and coils i replaced both crank seals and it runs perfect again. i think it was the clutch side as there was a small amount of oil seeping out but wasnt sure if it was grease
Reply With Quote
  #748  
Old 04-30-2013, 12:17 PM
T_Raw T_Raw is offline
Motorized Bicycle Member
 
Join Date: Mar 2013
Location: Navarre, Florida
Posts: 21
Default Re: Motorized Bicycle Take a Tip...Leave a Tip

what exactly are the crank seals
Reply With Quote
  #749  
Old 04-30-2013, 01:35 PM
crassius crassius is offline
Motorized Bicycle Elite Member
 
Join Date: Sep 2012
Location: USA
Posts: 3,017
Default Re: Motorized Bicycle Take a Tip...Leave a Tip

the crankcase is sealed all around its edges by those bolts you mentioned - at the two holes where the ends of the crank stick out of the case, there are two rubber seals to prevent leaking there
Reply With Quote
  #750  
Old 04-30-2013, 09:53 PM
JTona23 JTona23 is offline
Motorized Bicycle Newbie
 
Join Date: Feb 2013
Location: Australia
Posts: 4
Default Re: Motorized Bicycle Take a Tip...Leave a Tip

just wondering how port matching the inlet and exhaust ports of a 2-stroke will further increase engine efficiency
Reply With Quote
Reply

Tags
advice, bicycle, motorized, repair

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 08:12 AM.


Sponsors

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
MotorBicycling.com