chainsaw bicycle

assquatch20 · 10-04-2009, 10:36 PM

I've recently gotten a schwinn stingray bike with a homelite xl 12 motor on it. the motor seems to have an issue in compression or fuel (can't hardly get it started, then keep it running) but my question is in the area of gearing.

I was told that it might need a new clutch, but i'd like to try the sprockets first. it's got the large bicycle sprocket from up front located in the back now and a much smaller sprocket on the motor, but it doesn't seem to have much pull at all, but does much better without the chain on.

any ideas on what this might specifically be? could it be tied in with my starting problem?

**octaneman** · 10-05-2009, 04:40 AM

Hi assquatch20

When you changed the larger sprocket from the front to the back , you also changed the gearing ratio. There won't be any "pull" because the smaller gear on the motor will now have to make two revolutions in order for the rear gear to make one. Follow the original recommendation and have the clutch checked out.

post back your findings.

assquatch20 · 10-17-2009, 09:38 PM

so i've went through it on a compression test and i'll probably just get gaskets, maybe a carb rebuild, and maybe new rings; it's time for that on this thing anyway.

new problem. getting the casing off to have a look at the lower end, i ran into a couple stripped bolts, and broke an extractor head off on the first try. i'll probably try heating to get it outta there if a hammer and punch doesn't work, but the casing is made of magnesium.

i suppose if you know why i'm worried to take a blowtorch to that, maybe you can tell me whether or not it'll actually burn me alive? i'm not sure if magnesium only burns in powder form or what, but some advice on whether or not to do this would be great. i highly value my epidermis and nerve endings.

**Basementgeek** · 10-18-2009, 07:29 PM

A torch should be fine, just warm it and not try to melt it.

BG

**K-B** · 10-19-2009, 03:59 AM

Like BGeek said, if you use a torch just take it real easy.

Magnesium like that will burn if heated enough and in contact with open flame, so do be careful. And if it does start to burn, do not put water on it.

assquatch20 · 10-19-2009, 06:26 PM

well if i need to weld a chunk on my broken extractor tip to get it outta there, would that be too much heat to have around magnesium?

Vatar · 10-19-2009, 06:59 PM

I wouldn't be worried usually it is a non flammable alloy of magnesium and some other metal welding onto the extractor wont set your engine ablaze. But if it does well then I guess your problem solved itself.

BTW: It takes a good amount of energy to get cast magnesium to burn you are right that powdered magnesium burns easier.

10-04-2009, 10:36 PM	#1 (permalink)
assquatch20 Registered User Join Date: Aug 2008 Location: Tennessee Posts: 4 OS: XP Service Pack 2	chainsaw bicycle I've recently gotten a schwinn stingray bike with a homelite xl 12 motor on it. the motor seems to have an issue in compression or fuel (can't hardly get it started, then keep it running) but my question is in the area of gearing. I was told that it might need a new clutch, but i'd like to try the sprockets first. it's got the large bicycle sprocket from up front located in the back now and a much smaller sprocket on the motor, but it doesn't seem to have much pull at all, but does much better without the chain on. any ideas on what this might specifically be? could it be tied in with my starting problem?

10-05-2009, 04:40 AM	#2 (permalink)
octaneman Mentor Home Support, Gearhead Automotive Center Join Date: May 2009 Posts: 541 OS: WINXP	Re: chainsaw bicycle Hi assquatch20 When you changed the larger sprocket from the front to the back , you also changed the gearing ratio. There won't be any "pull" because the smaller gear on the motor will now have to make two revolutions in order for the rear gear to make one. Follow the original recommendation and have the clutch checked out. post back your findings. Last edited by octaneman; 10-05-2009 at 04:49 AM.

10-17-2009, 09:38 PM	#3 (permalink)
assquatch20 Registered User Join Date: Aug 2008 Location: Tennessee Posts: 4 OS: XP Service Pack 2	Re: chainsaw bicycle so i've went through it on a compression test and i'll probably just get gaskets, maybe a carb rebuild, and maybe new rings; it's time for that on this thing anyway. new problem. getting the casing off to have a look at the lower end, i ran into a couple stripped bolts, and broke an extractor head off on the first try. i'll probably try heating to get it outta there if a hammer and punch doesn't work, but the casing is made of magnesium. i suppose if you know why i'm worried to take a blowtorch to that, maybe you can tell me whether or not it'll actually burn me alive? i'm not sure if magnesium only burns in powder form or what, but some advice on whether or not to do this would be great. i highly value my epidermis and nerve endings.

10-18-2009, 07:29 PM	#4 (permalink)
Basementgeek Moderator, Home Support Join Date: Feb 2005 Location: Central Ohio, USA Posts: 1,470 OS: XP Pro SP2/Vista Ultimate SP2 Blog Entries: 3	Re: chainsaw bicycle A torch should be fine, just warm it and not try to melt it. BG __________________ Donating to the forum keeps TSF free for all. Proud member of ASAP

10-19-2009, 03:59 AM	#5 (permalink)
K-B Moderator, Linux Join Date: Oct 2005 Location: NY Posts: 2,873 OS: Vista, Ubuntu My System	Re: chainsaw bicycle Like BGeek said, if you use a torch just take it real easy. Magnesium like that will burn if heated enough and in contact with open flame, so do be careful. And if it does start to burn, do not put water on it. __________________

10-19-2009, 06:26 PM	#6 (permalink)
assquatch20 Registered User Join Date: Aug 2008 Location: Tennessee Posts: 4 OS: XP Service Pack 2	Re: chainsaw bicycle well if i need to weld a chunk on my broken extractor tip to get it outta there, would that be too much heat to have around magnesium?

10-19-2009, 06:59 PM	#7 (permalink)
Vatar Registered User Join Date: Oct 2009 Posts: 26 OS: 2000 Professional	Re: chainsaw bicycle I wouldn't be worried usually it is a non flammable alloy of magnesium and some other metal welding onto the extractor wont set your engine ablaze. But if it does well then I guess your problem solved itself. BTW: It takes a good amount of energy to get cast magnesium to burn you are right that powdered magnesium burns easier.