415 Chain simply doesn't work with my stock Grubee...

GoldenMotor.com
H

his196

New Member
Jun 19, 2011
99
0
0
Thousand Oaks, CA
Ok, stock 48cc Grubee, installed and tuned right.

Came with original bike chain, worked fine.

Bought a 415 ahttp://motorbicycling.com/newthread.php?do=newthread&f=39nd measured it right, installed it with a spring-loaded chain tensioner.

The chain simply won't wrap through the sprocket smoothly.

It hangs up on the tight circumference of the stock sprocket and gets stuck at every revolution.

What's up? Any comments?

Chris B..shft.
 
DuctTapedGoat

DuctTapedGoat

Active Member
Dec 20, 2010
1,179
10
38
38
Nampa Idaho
It's just new stuff. Walk your bike for 100 yards with the clutch in. Then pedal it for a few hundred yards with the clutch in. Make sure your alignment is good when you start and at intervals throughout. It'll break in.
 
F

flatblack

New Member
May 22, 2011
374
1
0
Fairfax, VA
There may be some grinding involved as well. I know some people have to remove a bit of material from the bottom of the case and some on the cover.
 
H

his196

New Member
Jun 19, 2011
99
0
0
Thousand Oaks, CA
Thanks.

It's actually not grinding anywhere, but when it's revolving around the small crankshaft, it's as if it doesn't "like" being told to navigate such a small diameter wheel, and so upon entry it's not 'catching' well every few revolutions, and upon exit, it's not 'unfolding' easily off the last tooth holding it.

My tension is perfect as can be with a nice spring loaded chain tensioner. I'll try to upload some pics. I've got strong tension on the lower chain and light, counter-tension on the upper so I have about zero chain jump/misalignment, but it's not too tight.

Here's a link to some pics of the tensioner with the old chain on, that works great: https://picasaweb.google.com/110058597097031274715/BikeChainTensioner

Thanks.
brnot
 
S

stickerbush

New Member
Jun 22, 2011
33
0
0
Pacific Northwest
I'm having no problems running a 415 chain on my 48cc Grubee Skyhawk. I'm not using a chain tensioner. I did notice that the chain was very stiff at first, but loosened up after being run for a bit.
 
DuctTapedGoat

DuctTapedGoat

Active Member
Dec 20, 2010
1,179
10
38
38
Nampa Idaho
Like I said, just burn through it with the motor disengaged to get the surfaces to mate a bit, always watching and listening to it just get better and better. Once it sounds and feels and looks good, fire it up.

This happened to me a couple weeks ago when I dropped a 415H on a grubby motor, I know exactly what you're talking about.
 
H

his196

New Member
Jun 19, 2011
99
0
0
Thousand Oaks, CA
Ok all, thanks for the advice.

Gonna reload the 415 and try and break it in, as suggested.

Alignments fine, so not side/lateral rub anywhere, it's the actual sprocket teeth and the chain 'popping'/'not seating' all the way down on the tooth upon entry, and then 'sticking'/'grabbing' upon release of the revolution.

Working the heck on my tensioner, poor little thing.

Hopefully, it'll break in.

Will advise, probably do in next few days.

PS: My only reason for using a 415 is I'm 5'8, 190lbs. and don't want to have the lighter chain snap on me at speed (for simply too much pull).
 
F

flatblack

New Member
May 22, 2011
374
1
0
Fairfax, VA
Whoa! That's quite the tensioner. Why such a complicated device? If possible, I'd remove some links and only run the bottom, if even that.
 
H

his196

New Member
Jun 19, 2011
99
0
0
Thousand Oaks, CA
Hey flatblack,

I found that the rigid/original tensioner didn't compensate for lateral slip on the top portion of the chain, nor the slack/tight/slack/tight on the top chain with the two-stroker.

When I added a springloaded bottom side tensioner, it was 1000 times better, but I still had top side lateral and slack/tight problems, so I added the upward, spring-loaded tensioner portion and now, the chain runs perfect, with almost zero lateral, and about zero tight/slack. Nice thing is the upward portion runs in conjunction with the necessary action of the lower, so they work together, not independent.

Also, the angle of the motor mount required me to get two, nice long parallel lengths coming out of the motor sprocket and staying nice and straight to avoid ANY movement whatsoever.

No more links avail. to be removed, even without any tensioner.

It's actually great! No more worries about the chain popping off.
 
Wm Holden

Wm Holden

New Member
Jun 1, 2011
358
2
0
Ventura California
his196 said:
Ok last question about Dremels for Wm:

What's the lowest voltage/rpm model that is good for metal-working?

I found a cheapo for $40 here:
Amazon.com: Dremel 7700-1/15 MultiPro 7.2-Volt Cordless Rotary Tool Kit: Warehouse Deals

But not sure it's got the juice I need to grind metal.

Thoughts?
Click to expand...
I don't have the specs in my head...but it won't really take much...youre not port matching or anything thick...just knocking the square tips off the shoulder of the tooth on top...the chain will just about do it itself over time...thats why some are just saying to run it.
 
S

stickerbush

New Member
Jun 22, 2011
33
0
0
Pacific Northwest
I guess I just let the chain do the work for me, didn't use a Dremel or file. it was really stiff at first but loosened up pretty quickly. It's a lot less noisy now too (after ~ 20 miles).
 
You must log in or register to reply here.
Top Bottom