Motorized Bicycle Engine Kit Forum  
Register FAQ Members List Calendar Mark Forums Read




Sponsors
To be a sponsor Contact Us
Donations accepted!
Our Forums


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

Motorized Bicycle General Discussion Topics on bicycle engine kits, help articles, repair and modifications for your motorized bicycles

Compression after 9 Months


Discussion at Motorized Bicycle Engine Kit Forum in the Motorized Bicycle General Discussion forum. Howdy Mates, Its been awhile. I have had this 80cc running now for about 9 Months, and put a few ...
Reply
 
LinkBack (1) Thread Tools Display Modes
  1 links from elsewhere to this Post. Click to view. #1 (permalink)  
Old 03-31-2009, 03:39 PM
Motorized Bicycle Elite Member
 
Join Date: Jun 2008
Posts: 204
Default Compression after 9 Months

Howdy Mates, Its been awhile.

I have had this 80cc running now for about 9 Months, and put a few miles on it a week,

to give you an idea, I doubt that I have used more than 7 gallons of gas, but recently

noticed, it runs OK, but it seems a little harder to kick off, meaning, . . It used to pop off easily

and start right up, however now it doesn't fire on the the first try, after a hardy pedaling,

it fires and starts up. Has the compression changed that much or should I start checking

further?
Reply With Quote
  #2 (permalink)  
Old 03-31-2009, 03:54 PM
azbill's Avatar
Motorized Bicycle Elite Member
 
Join Date: May 2008
Location: Fountain Hills, Arizona
Posts: 1,323
Default Re: Compression after 9 Months

is the gas mix old ?
2stroke mix gets stale pretty quickly (within 2 weeks, I think)
check you plug as well ...might be fouled
mine has a little under 4k on it and takes forever to start now
(I should shoot it and put it out of it's misery, but I need it till my new drivetrain comes in)
__________________
Bill
EZ Motorbike Dealer - Fountain Hills, AZ
www.ezmotorbike.com
azgrampa@gmail.com

Last edited by azbill : 03-31-2009 at 03:57 PM.
Reply With Quote
  #3 (permalink)  
Old 03-31-2009, 03:58 PM
Motorized Bicycle Elite Member
 
Join Date: Jun 2008
Posts: 204
Default Re: Compression after 9 Months

I guess it could be as much as two weeks, but that would be about it.

I'll try to spray some start up fluid into it next time to see if it will kick

faster and easier.
Reply With Quote
  #4 (permalink)  
Old 03-31-2009, 05:35 PM
Pablo's Avatar
Master Bike Builder & Forum Sponsor
 
Join Date: Dec 2007
Location: Duvall, WA PNW
Posts: 2,847
Default Re: Compression after 9 Months

Sounds like a tired plug? What plug? How old?
Reply With Quote
  #5 (permalink)  
Old 03-31-2009, 06:42 PM
Motorized Bicycle Elite Member
 
Join Date: Jun 2008
Posts: 204
Default Re: Compression after 9 Months

Hi Pablo,
It's an AGK B6HS, its been in for 7 Months, and is pretty well carbon coated, but not really caked. Whatya think ?
Reply With Quote
  #6 (permalink)  
Old 03-31-2009, 07:09 PM
Pablo's Avatar
Master Bike Builder & Forum Sponsor
 
Join Date: Dec 2007
Location: Duvall, WA PNW
Posts: 2,847
Default Re: Compression after 9 Months

NGK right? I would change plugs. Low cost, simple things first.
Reply With Quote
  #7 (permalink)  
Old 04-01-2009, 10:59 AM
Sydneysider's Avatar
Motorized Bicycle Elite Member
 
Join Date: Mar 2009
Location: Sydney
Posts: 187
Default Re: Compression after 9 Months

I had some similar probs, and found the muffler was chocker blocked with carbon.. cleaned it right up and it fired up right away and the power was back up again. Hope this helps.
__________________
"....dunno what I did to my engine the other day but now my rear tyre wears out real quickly..."
Reply With Quote
  #8 (permalink)  
Old 04-01-2009, 11:15 PM
Motorized Bicycle Elite Member
 
Join Date: Jun 2008
Posts: 204
Default Re: Compression after 9 Months

OK, Thanks I'll get on it, . .

It more than likely is one of the two of those, The things is with most start up even if it needs another try, you can here the compression stroke exhausting, But on the occasion I am getting nothing but a slow gruel to a hard pedal stop, I do not hear the compression escaping.

I'm not sure exactly what to think about that, . .?

Is that do to the fact that a burn combustion is pushing out the exhaust valve with enough pressure that it is causing the sound of exhaust escape?

If so, I guess then a clogged muffler would have similar results,

I think you guys know your 2 strokes.

I'll let you know.
Reply With Quote
  #9 (permalink)  
Old 04-01-2009, 11:49 PM
Goat Herder's Avatar
Motorized Bicycle Elite Member
 
Join Date: Apr 2008
Location: Albuquerque
Posts: 1,202
Default Re: Compression after 9 Months

Does it have power after warming it up? Mine was pretty wore out for compression at 5000 miles when It finally just didn't have power but it would start right up! Maybe spark dunno. I saw old gas give these CH a bad attitude.
Reply With Quote
  #10 (permalink)  
Old 04-02-2009, 12:23 AM
Sydneysider's Avatar
Motorized Bicycle Elite Member
 
Join Date: Mar 2009
Location: Sydney
Posts: 187
Default Re: Compression after 9 Months

Quote:
Originally Posted by Wheel Rush View Post
OK, Thanks I'll get on it, . .

It more than likely is one of the two of those, The things is with most start up even if it needs another try, you can here the compression stroke exhausting, But on the occasion I am getting nothing but a slow gruel to a hard pedal stop, I do not hear the compression escaping.

I'm not sure exactly what to think about that, . .?

Is that do to the fact that a burn combustion is pushing out the exhaust valve with enough pressure that it is causing the sound of exhaust escape?

If so, I guess then a clogged muffler would have similar results,

I think you guys know your 2 strokes.

I'll let you know.
Most likely. I found with mine when I opened full throttle at idle, it would rev extremely slowly at first but once it hit that higher rev, it would shoot right up meaning that there was enough pressure to escape out of the engine.
__________________
"....dunno what I did to my engine the other day but now my rear tyre wears out real quickly..."
Reply With Quote
Reply


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

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

LinkBacks (?)
LinkBack to this Thread: http://motorbicycling.com/f3/compression-after-9-months-7101.html
Posted By For Type Date
Biking Bis - Bicycle Touring and More :: Feed Zone This thread Refback 03-31-2009 05:28 PM


All times are GMT -5. The time now is 01:31 AM.


Sponsors
To be a sponsor Contact Us


Powered by vBulletin® Version 3.6.8
Copyright ©2000 - 2010, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO 3.3.2
Motorized Bicycle Engine Kit Forum


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71