34 tooth sproket

Scol

Member
Jan 10, 2014
44
0
6
Ireland
I have gone back to a 2 stroke engine as my 4 stroke was not up to the task of pulling me up hill around my area even on the flat I have to cycle to help it along. So I've gone back to 80cc 2 stroke engine just ran in with the standard 44 tooth sprocket.

I have a 34 tooth sprocket I was thinking of fitting has anyone else done this ?
Does this put too much pressure on the engine ?
I don't mind peddling the bike giving it a helping hand up hills etc.
would the bike be too fast ?

.trk
 

ultralight01

New Member
Oct 30, 2016
337
0
0
Hood River, Oregon
It will barely have enough torque but ok. People do it. You'll need to pedal a lot more to avoid stressing the engine or unsuccessfully trying to start it and skidding to a stop.
 

Kartooo

Member
Nov 18, 2016
178
3
18
MA
i like 40, just right, the goldielocks sprocket.
torque + speed
 
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Amarion1

Member
Sep 15, 2012
99
2
8
33
Bellingham WA
Ive run a 36 tooth. On my 700c i hit 40 on a straight and peddal assisted it up the biggest hill in the city and didnt break a sweat. On my 26er i got up to 35 on a straight. Didnt test the hill climb. But could get moving from a stand still
 

leo

Member
Jul 20, 2015
250
0
16
southern wv
if you live in an area that is all flat you will be fine. if you have hills, you will need a bigger gear. i had a 32t on mine for a minute, it hit 47mph on level ground but wouldn't even climb the modest incline to my house. i have a 56t on now, top speed is around 25mph now, but it climbs much better. i take it out on the hatfield mccoy trails all the time and it climbs some pretty steep stuff.

it all depends on the terrain you plan to ride on. gear for reality.
if not, you will eventually wind up undoing all that work...
 

KCvale

Well-Known Member
Feb 28, 2010
3,967
53
48
Phoenix,AZ
I have gone back to a 2 stroke engine as my 4 stroke was not up to the task of pulling me up hill around my area even on the flat I have to cycle to help it along.

I have a 34 tooth sprocket I was thinking of fitting has anyone else done this ?
You have altering terrain and trying to pick a set gear ratio.
That is like having a manual 5-speed car and putting it one gear for all driving.
It only does one specif thing well, and a 35 would only be good for going fast downhill.

If you want to go fast AND climb hills well you just need adjustable gears.

This is easy on bicycle that that already has hub gears, you just 'Jackshaft' you engines output to the right hand pedal system.

That ~50cc 4-stroke you wrote off for not having enough power?

They work great if you can shift the gear ratio on the fly like most bicycles can with human power.

With a 5-speed internal shifting hub these ~50cc shifters I am building will jump out in traffic and hit 25mph is like 6 seconds, hit 40+mph on the flats, and still climb a 6% grade @20mph steady with NO pedal help.




A 66cc 2-stroke like you just got, even better.



More power but the same gearing, the numbers just go up.

I just implore anyone looking to improve their performance with gears think about BRAKES first!

The eyepoping thrill you get with the power can and will wipe that smile away if you can't stop as fast as you can go guys, really.


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KCvale

Well-Known Member
Feb 28, 2010
3,967
53
48
Phoenix,AZ
The ONLY drawback is price
Not entirely, there are some skills and specialty tools required to make them go, and not a project for total nOOb with poor tools.

single speed is cheap, but gears are FREAKING AWESOME.
When the budget is not a limiting factor, there are ways to get some outstanding performance from ~legal size engines ;-}