am i crazy or is this the best idea or the worst idea to put a husky top end on one of these bikes

babiegirly

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Jan 13, 2020
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ok so i am wondering if im the only one to have thought of this or is it a bad idea or what cuz im looking at this cheep assed chinese head and i am looking at the husky heads on amazon both are 50 mm or i would even like to go up to maybe the 52 mm if the bolts would line up cuz it looks like the porting from a Suzuki or husky would fit much more closely to my crank case then the stock head does anyone thoughts on this any one ever think to try putting the top end from a chainsaw on one of there my first thoughts are it would be way better
 


Akutey

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Dec 10, 2018
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It's been tried and it won't work. Part's don't align with even if bolt patterns do, the engine geometry will be off causing those ports to be paper weights and lastly you need to have to correct your huge crankcase volume.
 

Street Ryderz

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Oct 14, 2016
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ok so i am wondering if im the only one to have thought of this or is it a bad idea or what cuz im looking at this cheep assed chinese head and i am looking at the husky heads on amazon both are 50 mm or i would even like to go up to maybe the 52 mm if the bolts would line up cuz it looks like the porting from a Suzuki or husky would fit much more closely to my crank case then the stock head does anyone thoughts on this any one ever think to try putting the top end from a chainsaw on one of there my first thoughts are it would be way better
Not the first and and I'll bet not the last!
 

babiegirly

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Jan 13, 2020
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yeah that's actually what i wanna do eventually i was thinking of a 90 cc Hilty concrete saw be expensive but really easy since there already belt drive would in theory just have to attach a pully to the rear and mount the motor would be my first choice, unfortunately, i don't have one at the moment honestly the main reason i ask is mostly cuz it looks like the jug from a Suzuki 100 would actually be a better fit than the stock one but i can always just do a little port polishing and stock one should be fairly close wish i had a working camera to post pictures unfortunately
 

Street Ryderz

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yeah that's actually what i wanna do eventually i was thinking of a 90 cc Hilty concrete saw be expensive but really easy since there already belt drive would in theory just have to attach a pully to the rear and mount the motor would be my first choice, unfortunately, i don't have one at the moment honestly the main reason i ask is mostly cuz it looks like the jug from a Suzuki 100 would actually be a better fit than the stock one but i can always just do a little port polishing and stock one should be fairly close wish i had a working camera to post pictures unfortunately
Here's the issues with that type of build that many just don't seem to understand,these are 2 stroke and the bigger is better theory doesn't really apply here.This is because the chainsaw/quick cut cylinders are designed to make their power at peak rpm and compared to other single cylinder engines of similar displacement for performance engines lack hp and torque lower in the range witch is needed for single speed bikes! The biggest sthil cylinder (ms880) is only rated at 7hp and we can make 10 hp from a properly done china girl that makes more torque at lower rpm to be able to pull through the load of a single gear.Then we have the loss of ccr due to case volume difference and this loss takes away from low end power also due to the lack of pumping efficiency in that range.Next there is the geometry difference in that most saw's have a short stroke being 34mm on average and this makes the port timing and the time over area all wrong and needing to be corrected for the longer stoke that is commonly used,these are the main two issues that alter it's performance ability.Then there are the fitting issues where the bdc doesn't line up,the wrist pin is a different size and alot of machine work needs to be done for them just to fit on the case.I personally think it's not worth the time or money when for the same money or less and far less work and frustration you can have the china cylinder corrected and treated with nikasil that will last as long as any quality cylinder (when used properly) and make more usable power thru out the range.
 

Chainlube

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Jan 5, 2020
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1,658
I have a friend that put a 33 cc chainsaw engine on a kids bike. The kid had to peddle madly, but once up to speed, it went fast.
 

ESmalik

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Oct 22, 2019
Messages
77
It's been done many times already. There's a few builders out there that specialize in husky and stihl cylinders. There's definitely a lot of work to get
these things to work but they can be extremely rewarding if done correctly.
92255
92256
92257
 

babiegirly

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Jan 13, 2020
Messages
13
Here's the issues with that type of build that many just don't seem to understand,these are 2 stroke and the bigger is better theory doesn't really apply here.This is because the chainsaw/quick cut cylinders are designed to make their power at peak rpm and compared to other single cylinder engines of similar displacement for performance engines lack hp and torque lower in the range witch is needed for single speed bikes! The biggest sthil cylinder (ms880) is only rated at 7hp and we can make 10 hp from a properly done china girl that makes more torque at lower rpm to be able to pull through the load of a single gear.Then we have the loss of ccr due to case volume difference and this loss takes away from low end power also due to the lack of pumping efficiency in that range.Next there is the geometry difference in that most saw's have a short stroke being 34mm on average and this makes the port timing and the time over area all wrong and needing to be corrected for the longer stoke that is commonly used,these are the main two issues that alter it's performance ability.Then there are the fitting issues where the bdc doesn't line up,the wrist pin is a different size and alot of machine work needs to be done for them just to fit on the case.I personally think it's not worth the time or money when for the same money or less and far less work and frustration you can have the china cylinder corrected and treated with nikasil that will last as long as any quality cylinder (when used properly) and make more usable power thru out the range.
ok you make good sence here how about the head from a suzuki ax100 just wondering cuz it looks like it could alomst be the mother of the motor i got and a dirtbike head woulkd likely be more well suited for the application thoughts on that maybe
 

Street Ryderz

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ok you make good sence here how about the head from a suzuki ax100 just wondering cuz it looks like it could alomst be the mother of the motor i got and a dirtbike head woulkd likely be more well suited for the application thoughts on that maybe
The bcd is different and has a 50mm bore.
 
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