| Sponsors
|  | |
Donations accepted to help with server fees and other expenses. Thank you!
| | |
| Motorized Bicycle General Discussion Topics on bicycle engine kits, help articles, repair and modifications for your motorized bicycles |
Machining the head/ Boosting compression
Discussion at Motorized Bicycle Engine Kit Forum in the Motorized Bicycle General Discussion forum. I am considering machining the top of the cylinder (the head) down by a millimeter or two on a lathe ...  | | 
06-24-2008, 09:08 PM
| | Master Motorized Bicycle Builder | | Join Date: Jun 2008 Location: Australia
Posts: 108
| |  Machining the head/ Boosting compression
I am considering machining the top of the cylinder (the head) down by a millimeter or two on a lathe to boost compression. Has anybody tried this? There is a bloke from Australia who has apparently with success.
Shouldn't be too difficult and should work fine... bit of a risk tho! Hmmmmm |
06-24-2008, 09:10 PM
| | Master Motorized Bicycle Builder | | Join Date: Jun 2008 Location: Australia
Posts: 108
| | Re: Machining the head/ Boosting compression
Here is the link... Check out "Lisdale Flyer" what a BEAST!! ZBox engine innovations 2008 |
06-24-2008, 11:54 PM
|  | Master Motorized Bicycle Builder | | Join Date: Jun 2008 Location: Longmont, CO
Posts: 1,084
| | Re: Machining the head/ Boosting compression
I was just thinking about this today, wondering if it could be done. |
06-25-2008, 06:57 AM
| | Master Motorized Bicycle Builder | | Join Date: Jun 2008 Location: Australia
Posts: 108
| | Re: Machining the head/ Boosting compression
Shouldn't be too hard Just take the cylinder to a metal turner. I think it would be a good idea to tread cautiously. The extra compression might rip a head bolt right out of the engine block! I stripped the engine block thread just by over tightening a while back, luckily I had it heli-coiled back in place |
06-25-2008, 08:28 AM
|  | MODERATOR | | Join Date: Jan 2008 Location: Ashtabula county, Ohio
Posts: 4,245
| | Re: Machining the head/ Boosting compression
I don't know about a "mm or two". That would be a bit excessive.
3mm would be 1/8th of an inch! Math for the Toolbox. SAE to Metric Conversion.
__________________
If it ain't broke, and you mess with it long enough, it will be.
Last edited by Bikeguy Joe : 06-25-2008 at 08:31 AM.
|
06-25-2008, 09:49 AM
|  | Master Bike Builder & Forum Sponsor | | Join Date: Dec 2007 Location: Duvall, WA PNW
Posts: 1,708
| | Re: Machining the head/ Boosting compression
Back in the day we would surface grind or mill heads.....dunno about the head in a lathe.... |
06-25-2008, 10:51 AM
|  | Moderator | | Join Date: Jan 2008 Location: Pampa, Texas
Posts: 1,382
| | Re: Machining the head/ Boosting compression
Norman has a piece of glass with sandpaper glued to it that he uses. It removes metal real nice and slow. He keeps it wet and soapy...................
__________________ There are only 10 kinds of people in this world. Those that understand binary and those that don't............
Become a Forever Family, it'll change your life. http://www.galtx.org/ http://bdconner.com |
06-25-2008, 10:55 AM
| | Master Bike Builder & Forum Sponsor | | Join Date: Dec 2007 Location: Duvall, WA PNW
Posts: 1,708
| | Re: Machining the head/ Boosting compression
That's where I'm going, the Norman way!! |
06-25-2008, 11:09 AM
|  | Santa Cruz Scooter Works | | Join Date: Jan 2008 Location: Nor*Cal
Posts: 695
| | Re: Machining the head/ Boosting compression
We done a few and the best one we did was around 70 thousand of an inch. We even redomed one and it works for a little bit but we found out the the head bolts (which are made of cheap metal) stretches. Then leaks and blown head gaskets occur. |
06-25-2008, 11:41 AM
| | Master Bike Builder & Forum Sponsor | | Join Date: Dec 2007 Location: Duvall, WA PNW
Posts: 1,708
| | Re: Machining the head/ Boosting compression
Quote:
Originally Posted by Easy Rider  We done a few and the best one we did was around 70 thousand of an inch. We even redomed one and it works for a little bit but we found out the the head bolts (which are made of cheap metal) stretches. Then leaks and blown head gaskets occur. | More good info. Note to self, get new studs. | | Thread Tools | | | | Display Modes |  Linear Mode | 
Posting Rules
| You may not post new threads You may not post replies You may not post attachments You may not edit your posts
HTML code is Off | | | All times are GMT -5. The time now is 01:03 PM. | |
|
