85cc monkey bike upgrade to 110cc? Will it work
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85cc monkey bike upgrade to 110cc? Will it work
Any advice appreciated
Bike is a skyteam st90 monkey bike 85cc. Similar if not same as c90 I’ve had in the past?
Don’t want to buy parts and not fit
Thanks
Bike is a skyteam st90 monkey bike 85cc. Similar if not same as c90 I’ve had in the past?
Don’t want to buy parts and not fit
Thanks
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- Posts: 593
- Joined: Tue Nov 20, 2012 1:16 am
- Rides:: Z50,cf70,msx and an auld german 1200gs
- Location: Belfast, Northern Ireland
Re: 85cc monkey bike upgrade to 110cc? Will it work
Hello Steve and welcome aboard.
With the 107cc kit fitting on the 85cc Honda cub 12v engine there is a strong chance it will work.
Early 12v cub engines need the casings opened up manually,but later ones are already wider to accept the 107 barrels bigger skirt,so I'll interested to know how yours appear.
Have you looked at the kit from petrolscooter?
Colin J
With the 107cc kit fitting on the 85cc Honda cub 12v engine there is a strong chance it will work.
Early 12v cub engines need the casings opened up manually,but later ones are already wider to accept the 107 barrels bigger skirt,so I'll interested to know how yours appear.
Have you looked at the kit from petrolscooter?
Colin J
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- Posts: 11
- Joined: Fri Jan 29, 2021 11:50 pm
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Re: 85cc monkey bike upgrade to 110cc? Will it work
Thanks for the reply
Yes I’ve seen the kit from petrolscooter on eBay and it’s cheap but unsure how good it will be? Have you had any experience with these kits reliability wise. I would like to know if it will fit before disassemble and buying parts ideally? Thanks again
Yes I’ve seen the kit from petrolscooter on eBay and it’s cheap but unsure how good it will be? Have you had any experience with these kits reliability wise. I would like to know if it will fit before disassemble and buying parts ideally? Thanks again
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- Posts: 593
- Joined: Tue Nov 20, 2012 1:16 am
- Rides:: Z50,cf70,msx and an auld german 1200gs
- Location: Belfast, Northern Ireland
Re: 85cc monkey bike upgrade to 110cc? Will it work
Yes,I have already done a 1988 motor,but only covered around 500 miles on it,and I'm about to do a 1996 engine, both using those kits.Monkeysteve wrote: ↑Sat Jan 30, 2021 1:54 pmThanks for the reply
Yes I’ve seen the kit from petrolscooter on eBay and it’s cheap but unsure how good it will be? Have you had any experience with these kits reliability wise. I would like to know if it will fit before disassemble and buying parts ideally? Thanks again
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- Posts: 11
- Joined: Fri Jan 29, 2021 11:50 pm
- Rides:: Ktm 300
Re: 85cc monkey bike upgrade to 110cc? Will it work
Just taken mine apart and measurements seem right. Do you upgrade the intake or jets? If to what sizes. Thanks
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- Posts: 593
- Joined: Tue Nov 20, 2012 1:16 am
- Rides:: Z50,cf70,msx and an auld german 1200gs
- Location: Belfast, Northern Ireland
Re: 85cc monkey bike upgrade to 110cc? Will it work
I ran the standard issue 110/125cc pit bike 22mm carb and it was fine,but read others retained their standard cub carbs,19mm iirc,and upped the main jet slightly.Monkeysteve wrote: ↑Sat Jan 30, 2021 7:57 pmJust taken mine apart and measurements seem right. Do you upgrade the intake or jets? If to what sizes. Thanks
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- Posts: 11
- Joined: Fri Jan 29, 2021 11:50 pm
- Rides:: Ktm 300
Re: 85cc monkey bike upgrade to 110cc? Will it work
Any idea what size jet to go to?
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- Posts: 593
- Joined: Tue Nov 20, 2012 1:16 am
- Rides:: Z50,cf70,msx and an auld german 1200gs
- Location: Belfast, Northern Ireland
Re: 85cc monkey bike upgrade to 110cc? Will it work
There is guide in this forum that discusses this conversion, think they explain the jet sizes.
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- Posts: 11
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Re: 85cc monkey bike upgrade to 110cc? Will it work
Did it you have to modify the crankcase- make wider for barrel skirt? Measurements of the skirt seem it will just fit but think it will be close
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- Posts: 593
- Joined: Tue Nov 20, 2012 1:16 am
- Rides:: Z50,cf70,msx and an auld german 1200gs
- Location: Belfast, Northern Ireland
Re: 85cc monkey bike upgrade to 110cc? Will it work
I've only experience with bigger Chinese engines,but the later Honda c90 engine I'm about to do doesn't need the around 2mm excess removed to fit the 107 kit,but the earlier honda did.Monkeysteve wrote: ↑Sun Jan 31, 2021 11:48 amDid it you have to modify the crankcase- make wider for barrel skirt? Measurements of the skirt seem it will just fit but think it will be close