advice on motor size for friction drive bike

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Lane

New Member
Apr 10, 2021
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Hi everybody, My name's Lane. I'm new to this forum but I have been researching either getting a staton friction drive kit or building my own. I've found a ton of good information in the last week or so of studying this forum but I still have some questions. I'm new to bikes but I'm a gunsmith and am also just finishing successfully swapping a mercedes diesel engine into a ford ranger pickup so I have some decent mechanical skills. So I'm not worried about my ability to design and build a good reliable friction drive setup if I decide to go that route. However I have NO experience with motorized bicycles or these ultra small 25 to 50 cc engines and so I have no idea how much power they produce. I plan on using it both for ordinary riding like running into town to the store or whatever and also riding the backroads and trails in the mountains. so it will need to be capable of climbing hills carrying me and some gear in a pack strapped to the bike or possibly on my back. So a combined load of maybe a max of 210 pounds if I had the bike loaded really really heavy. However I also really want to be able get REALLY good gas mileage. So I guess what I'm asking is can you guys tell me what size engine and type of friction drive setup you are using and what kind of mileage you are getting as well as how it does climbing hills? I have no problem pedaling to help the motor out, especially on hills and I don't plan on driving super fast, maybe 25-30 max. So if I decide on a staton kit what kind of mileage could I expect with that kind of riding with the different size motors. I weigh like 140 pounds and probably a large part of the time I won't have the bike loaded with much more than me and a bit of extra fuel. Though like I said when I go into the backcountry the load will increase considerably.

thanks for any help you guys can offer!

Lane
 

curtisfox

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Dec 29, 2008
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I think you should use 50cc more power to turn the roller on back roads. Only trouble is on back country if there is any wet or rain the roller will slip, could do a rear rack chain drive.
Cannanball III built a friction drive with 3 speed hub for transmission, check him out ...........Curt
 

Lane

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Apr 10, 2021
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I'm definitely leaning towards the 50 cc at this point. I will have to try to find that 3 speed friction drive build. that sounds like a great setup. if I build my own rather than the kit I was planning on designing a setup that will easily switch from one size roller to another so I can have in affect multiple gears. probably not as handy as the three speed but it would allow a huge variation in gearing and allow it to be customized to the particular bike easily. If I build my own i'm thinking about using the honda GXH50 engine since it seems like it would be the easiest to use for the design I have in mind plus it seems to be much more sturdily built that the smaller GX50 used on the staton kits. It sounds like the one the staton kits use is very reliable too but I like the other one a bit better
 

curtisfox

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Dec 29, 2008
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You can buy a hole kit cheaper then a Honda motor LOL https://www.bikeberry.com/products/...ad-friction-drive-bicycle-engine-kit-4-stroke Use PayPal if you do or major credit card, for backup help, if you buy, as some have had troubles. I have a Honda I bought years ago, form Northern tool.com, setting on the shelf waiting for a new build.
You will find most older build in the DIY section cannanball2 has a lot of different builds, just go through the tread and look for his name under the headings. https://motorbicycling.com/threads/cannonballs-abbynormal-3speed.58233/ here is one. Another thought is Whizzer sheave belt drive on rear rack, cannanball2 has done one also. Belt drive is quiet, just do some study before you get to far along and then change you mind, LOL I believe all the older friction drives are in the diy section...........Curt
 

Lane

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Apr 10, 2021
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I’ve done some looking at the bikeberry kits. Have you had any experience with them? Do you know what brand motor they use or how reliable they are? As far as the Honda being more expensive, I’m usually willing to pay a bit more if it means not breaking down in the middle of nowhere.
 

Lane

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Apr 10, 2021
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I haven’t seen the whizzer sheave belt drive build but I will try to find it later. My main concern with any belt or chain drive is whether I will have trouble with broken spokes. I’ve heard that’s a problem with them. So far this is my favorite design. It’s a belt driven friction drive built by cannonball2.

 

curtisfox

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Dec 29, 2008
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Chain drive, best to use Sportsmanflyer his site is up on the side bar, sprocket adapter, would take care of it. I use to have a Monark twin back in the late 50's ( same as Whizzer only I think better ) You can get heavy wheels for Husky with 11 gage spokes, https://www.huskybicycles.com/bicycle-wheel-26-x-2125-with-shimano-coaster-brake-12-g-spokes.html Is just one the have 3 peed also, and with drum brake.

A lot of the troubles they are having are do to themselves, to beg a hurry and not getting it together right. Some guys on the forum have run rag joints for years and not a problem, just how you drive and all the high HP wild and woolly driving, just so you know, not trying to persuade you, there are faults on all builds.........Curt
 

Lane

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Apr 10, 2021
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yeah, I'm sure a lot of problems are caused by fast acceleration and generally over straining stuff. I'm not that kind of driver thankfully. I just want stuff to be simple and reliable even if I have to go a bit slower. Though these rough mountain roads aren't easy on any kind of vehicle no matter how carefully you drive it. Thanks for the advice

Also can anyone tell me what kind of mileage you're getting with a 49/50cc bike?
 

curtisfox

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Dec 29, 2008
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Old adds say a good 100mpg, but also be variation in that.
1618234642742.png

I have one of these and am working on it, carb troubles. Add is from 1960's............Curt
 

Jarrod

Member
Jun 13, 2019
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50
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50
Hi everybody, My name's Lane. I'm new to this forum but I have been researching either getting a staton friction drive kit or building my own. I've found a ton of good information in the last week or so of studying this forum but I still have some questions. I'm new to bikes but I'm a gunsmith and am also just finishing successfully swapping a mercedes diesel engine into a ford ranger pickup so I have some decent mechanical skills. So I'm not worried about my ability to design and build a good reliable friction drive setup if I decide to go that route. However I have NO experience with motorized bicycles or these ultra small 25 to 50 cc engines and so I have no idea how much power they produce. I plan on using it both for ordinary riding like running into town to the store or whatever and also riding the backroads and trails in the mountains. so it will need to be capable of climbing hills carrying me and some gear in a pack strapped to the bike or possibly on my back. So a combined load of maybe a max of 210 pounds if I had the bike loaded really really heavy. However I also really want to be able get REALLY good gas mileage. So I guess what I'm asking is can you guys tell me what size engine and type of friction drive setup you are using and what kind of mileage you are getting as well as how it does climbing hills? I have no problem pedaling to help the motor out, especially on hills and I don't plan on driving super fast, maybe 25-30 max. So if I decide on a staton kit what kind of mileage could I expect with that kind of riding with the different size motors. I weigh like 140 pounds and probably a large part of the time I won't have the bike loaded with much more than me and a bit of extra fuel. Though like I said when I go into the backcountry the load will increase considerably.

thanks for any help you guys can offer!

Lane
I've done a little bit of travel with the friction drive I've read through most of your post here the 79cc friction drives that I build for my friends can change drive rollers in under a minute.
16182685685683993916206994663680.jpg
16182686514598285116411212893029.jpg
1618268747900798957836735905357.jpg
 

Lane

New Member
Apr 10, 2021
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Old adds say a good 100mpg, but also be variation in that.
View attachment 106843
I have one of these and am working on it, carb troubles. Add is from 1960's............Curt

Well that's really encouraging. I definitely wouldn't be disappointed with well over 100 miles a gallon! Could you send a few pictures of your motor and how it's drive system works? Thanks a lot!
 

Lane

New Member
Apr 10, 2021
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I've done a little bit of travel with the friction drive I've read through most of your post here the 79cc friction drives that I build for my friends can change drive rollers in under a minute. View attachment 106846 View attachment 106847 View attachment 106848


Thanks a lot for the pictures! I really like the direct drive bikes like that. I love the simplicity. My one concern thou with the direct drive bikes like that where there is no support on the end of the roller is whether the pressure against the crank shaft bearing will cause premature wear and failure of the motor? have you ever had any problems with that and have you put large numbers of miles on yours that are built that way? I really like the idea of being able to just pull the bolt off and change rollers. What kind of mileage are you getting with one of the 79cc friction drives if you happen to know?
 
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Jarrod

Member
Jun 13, 2019
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Thanks a lot for the pictures! I really like the direct drive bikes like that. I love the simplicity. My one concern thou with the direct drive bikes like that where there is no support on the end of the roller is whether the pressure against the crank shaft bearing will cause premature wear and failure of the motor? have you ever had any problems with that and have you put large numbers of miles on yours that are built that way? I really like the idea of being able to just pull the bolt off and change rollers. What kind of mileage are you getting with one of the 79cc friction drives if you happen to know?
Over a hundred miles to the gallon yes we've used them a lot I used them to go touring .I've got a write-up in the friction drive section here of one of my trips the shaft coming out of the motor is 3/4 in or 5/8 in you're not putting no pressure on the bearings.
 

Lane

New Member
Apr 10, 2021
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Ok that’s great to know that even a motor that big is getting over a hundred. I’ll have to think about that design more since it doesn’t seem to hurt having the pressure on it
 
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hemmadroid

New Member
Feb 20, 2021
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I'm definitely leaning towards the 50 cc at this point. I will have to try to find that 3 speed friction drive build. that sounds like a great setup. if I build my own rather than the kit I was planning on designing a setup that will easily switch from one size roller to another so I can have in affect multiple gears. probably not as handy as the three speed but it would allow a huge variation in gearing and allow it to be customized to the particular bike easily. If I build my own i'm thinking about using the honda GXH50 engine since it seems like it would be the easiest to use for the design I have in mind plus it seems to be much more sturdily built that the smaller GX50 used on the staton kits. It sounds like the one the staton kits use is very reliable too but I like the other one a bit better
Hi. I have 2 japanese built 52cc 2 stroke motors complete. The better of the two is a Kawasaki model TEX54. It came from a backpack blower and is in exceptional condition. Original piston, rings and bore with very little wear. My other is same cc but from an echo blower backpack.I havnt disassembled the echo yet but know at most it might need $100 upper end rebuild.
What makes the Japanese better than Chinese motors is.........everything! the Japanese motors have way better design and metal quality. Also the crankshafts are like mini motorcycle cranks that rev high with little vibration compared to Chinese who use big heave pig iron discs with a few relief drilled holes for an attempted balance. night and day difference.
Im selling them both. kawasaki $150 and echo $90. John v. 805 940-9457 southern california.
 
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Lane

New Member
Apr 10, 2021
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Hey thanks for the offer. I'm planning on doing a 4 stroke though. I have more experience with them
 
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hemmadroid

New Member
Feb 20, 2021
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I hear you. I'd like to do a horizontal shaft Honda 200cc motor with jackshaft and use the mountain bikes cassette gears for better all around gearing. A real quiet exhaust at a low rpm would be a civilized ride.
 
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Lane

New Member
Apr 10, 2021
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Yeah making the exhaust nice and quiet is one thing I intend to put a lot of effort into on mine
 

Lane

New Member
Apr 10, 2021
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Would you guys recommend a front or rear wheel drive setup? I prefer rear wheel but I’m thinking that it may be easier having the motor on the front that having a pack strapped to the handlebars when I have gear with me for camping or whatever. I’m still not sure though cause it just doesn’t seem like it would be as practical
 

Jarrod

Member
Jun 13, 2019
50
50
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50
Would you guys recommend a front or rear wheel drive setup? I prefer rear wheel but I’m thinking that it may be easier having the motor on the front that having a pack strapped to the handlebars when I have gear with me for camping or whatever. I’m still not sure though cause it just doesn’t seem like it would be as practical
Looking at friction drive section my second attempt to cross country. Three separate builds I put in photos take a look.