New 80cc kit.

GoldenMotor.com
mapbike

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Best Toy Ever said:
How do you find out the chain size and the type of engine? It said 80cc. How fast can you go in the very beginning of an engines break in period?
Click to expand...
The reason I ask about type/brand of engine is because I remember seeing some of the Grubee engines listed as having the 410/ standard bicycle size chain, is the chain for the engine the same width as the chain on the pedal side of the bike?
If it is the same size then it is the 410 size chain if it is wider than the chain on the pedal side it is the 415 size chain which most of the kits have now days.

On a stock unbroken in engine running a 44T rear sprocket you should have a cruise speed of 20+ mph, don't push it and over rev the engine until you have run at least 2-3 full tanks of fuel through it.

Map
 
mapbike

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Here is a link that shows the differences in the chains

410 and 415 chains have the same pitch which means the space between the rollers but the width between the plates is what is different, 410/ standard bike chain is 1/8" width while the 415 chain is 3/16" width, a 415-3/16" chain will work fine on a sprocket designed for the 410-1/8" chain, but a 410-1/8" chain will not work on a sprocket designed for the wider 415-3/16" chain.

Heres the link to some chain specs.
http://www.azusaeng.com/chain/mcyclchn.html

Peace, Map
reddd
 
xseler

xseler

Well-Known Member
Apr 14, 2013
2,886
151
63
OKC, OK
My Grubee Skyhawk came with a 410 chain........so far it has worked great! I use a dry lube instead of oil or grease.

Out of the box, the engine felt comfortable at about 21mph with a brief top of around 27mph. Now, the comfortable speed is around 25mph with a top of 32mph. I've got a 44 tooth sprocket on 26X2.125 tires.

Good luck with getting it sorted out........once it happens, you'll be glad you built your bike!
 
mapbike

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
xseler said:
My Grubee Skyhawk came with a 410 chain........so far it has worked great! I use a dry lube instead of oil or grease.

Out of the box, the engine felt comfortable at about 21mph with a brief top of around 27mph. Now, the comfortable speed is around 25mph with a top of 32mph. I've got a 44 tooth sprocket on 26X2.125 tires.

Good luck with getting it sorted out........once it happens, you'll be glad you built your bike!
Click to expand...
From what I've seen, the 410 chain has the same strength rating as the 415 chain, I've never run the 410 chain because all my engine are setup for the wider chain, but I know that there are a boat load of the 410 chains being run out there and I assume most are having pretty good luck with them, I have read here on the forum of some that went through several 410 chains and then switched to the #41 or the #415 and quit breaking chains.

I've got some 420 chain I plan to use on my next build, its same size as the 415 but is considerably stronger and on the next bike I want the chain to be very strong since I'm gonna be shooting for a lot higher top cruise speed on my next bike.

Map
 
maniac57

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
0
memphis Tn
420 barely fits. You will need to grind under the front sprocket cover to gain clearance.
I use #41 HD roller chain from the local hardware store. $20 bucks for enough to fit two bikes.
 
B

Best Toy Ever

New Member
Jun 21, 2013
16
0
0
USA
It has a lot to do with the sprocket. I had one before it that was used extensively and then I decided to put the newer sprocket on the rim and then these problems started happening. It is also better to turn it around instead of the instructed way. Don't know why, but it is helpful. Makes absolutely no sense. So, I am going to put the older one back on. There is popping noises, but it doesn't come off. That said, this chain sucks. The other chain that I have that fits the older sprocket fits tight on the gear in the motor. So I have no choice right now, but to use this factory crap chain. My advice, get another chain with a new 80cc 2 Cycle Engine Motor Kit, that has a 44T Sprocket. Just have another option, just in case. Thank you all for you advise, respectively.
 
Last edited:
mapbike

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Best Toy Ever said:
It has a lot to do with the sprocket. I had one before it that was used extensively and then I decided to put the newer sprocket on the rim and then these problems started happening. It is also better to turn it around instead of the instructed way. Don't know why, but it is helpful. Makes absolutely no sense. So, I am going to put the older one back on. There is popping noises, but it doesn't come off. That said, this chain sucks. The other chain that I have that fits the older sprocket fits tight on the gear in the motor. So I have no choice right now, but to use this factory crap chain. My advice, get another chain with a new 80cc 2 Cycle Engine Motor Kit, that has a 44T Sprocket. Just have another option, just in case. Thank you all for you advise, respectively.
Click to expand...
You're very welcome and I know we all hope you get everything working smooth asap.

keep the rubber side down always!

Map
 
crassius

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
sure, they should all fit, but there are some with 10teeth & some with 11 - not a big deal usually tho

oops, almost forgot some have a wide woodruff key & some have a narrow one, so some filing on the key may be needed
 
MotorBicycleRacing

MotorBicycleRacing

Well-Known Member
Jul 28, 2010
5,844
109
63
SoCal Baby!!!
www.facebook.com
crassius said:
sure, they should all fit, but there are some with 10teeth & some with 11 - not a big deal usually tho

oops, almost forgot some have a wide woodruff key & some have a narrow one, so some filing on the key may be needed
Click to expand...
All the China girl kits come with a 10 tooth engine output sprocket.
There has never been an 11 tooth made or available as an upgrade.

The 10 tooth sprockets can vary in inside diameter and key size but you
have a good chance of it fitting so give it a try.
 
crassius

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
seen this happen due to rough spots in the casting - sometimes just a bit of finishing around the hole with a jeweler's file will smooth it out enough for the washer to seal, other times one needs to put a small fuel-proof o-ring in place of the washer
 
You must log in or register to reply here.
Top Bottom