4-stroke Grubee Sprocket Alignment

[Andrew735]

I have a 49cc 4-stroke grubee kit from bicycle-engines.com and i have it mounted on a schwinn jaguar. Everything is working except for that the engine drive sprocket and the sprocket on the back wheel wont line up. I have the engine moved over as far as i could, but they still wont line up. Can anyone help me?

 

[mickey]

Is the rear sprocket too far out, or too far in? Maybe post a photo, shot down the chain line from behind. Also, is it a standard 9 hole sprocket with rag rubber mounts? Does the sprocket have offset teeth?

 

[Andrew735]

Is the rear sprocket too far out, or too far in? Maybe post a photo, shot down the chain line from behind. Also, is it a standard 9 hole sprocket with rag rubber mounts? Does the sprocket have offset teeth?

the rear sprocket is too far out (about a cm). I tried posting a picture, but it didnt work. The rear sprocket is a standard 9 hole with rag rubber mounts. And the sprocket does have offset teeth and they are offsetting it away from the tire. I was thinking that moving the motor over would be my best bet because that would give more clearence between the chain and tire. What do you think?

 

[mickey]

And the sprocket does have offset teeth and they are offsetting it away from the tire.

So you already have the sprocket turned so that the teeth are inward? Do I understand that correctly? If not, turn it around.

If you increased the size of the center hole in the sprocket by filing or grinding, would that let the sprocket move further in on the spokes?

 

[Andrew735]

So you already have the sprocket turned so that the teeth are inward? Do I understand that correctly? If not, turn it around.

If you increased the size of the center hole in the sprocket by filing or grinding, would that let the sprocket move further in on the spokes?

The teeth are outward, but if i turn it around then the chain will rub the tire.

 

[mickey]

Hmm. What size tires do you have? Are they overly large? How about looking from the rear, with the engine over as far as it will go, will the chain clear the tire if the sprocket was lined up correctly? I mean, if you got the sprocket to line up, will it still clear the tire by 1/2 inch or so.

The best way to move the sprocket in is to turn it around. If you had another set of rubber moons, you could turn it around and use 2 sets on the outside of the spokes to bump it out a 1/4 inch, like some people do with the wide-tired stingrays.

Edit: I haven't ever seen the 4stroke kit in person. Are you thinking that you could elongate the mounting holes and slide the motor to the left? **edit** I see that you are. ** That seems doable. I wouldn't think the balance would be that far off but the mounting may be less secure.

Also, I think that you can buy non-offset sprockets that would let you half the distance that you move the teeth by flipping

 

[Andrew735]

Hmm. What size tires do you have? Are they overly large? How about looking from the rear, with the engine over as far as it will go, will the chain clear the tire if the sprocket was lined up correctly? I mean, if you got the sprocket to line up, will it still clear the tire by 1/2 inch or so.

The best way to move the sprocket in is too turn it around. If you had another set of rubber moons, you could turn it around and use 2 sets on the outside of the spokes to bump it out a 1/4 inch, like some people do with the stingrays.

The tire is a normal size. If the engine was over far enough the chain would clear the sprocket, but with the way it is now the chain angles in and rubs the tire. If i could move the engine over towards the sprocket side then it would line up, but it is over as far as it goes. I was thinking about grinding out the slots for bolting the motor down so i could move it over more.

 

[mickey]

I was thinking about grinding out the slots for bolting the motor down so i could move it over more.

Yeah, definitely doable. If that's the only way to clear the tire then you gotta do what you gotta do. As my Dad says, where theres no choices, there's no problem.

I think that the OC Choppers move their HT motors over to clear the fat tires so there's precedent.

Edit: I'm really surprised that if you are having trouble with normal sized tires, that others aren't having the same problem. Its a standard kit. Maybe you should hold off cutting until some of the guys that have mounted the Grubee 4stroke kit weigh in.

 

[Andrew735]

Yeah, definitely doable. If that's the only way to clear the tire then you gotta do what you gotta do. As my Dad says, where theres no choices, there's no problem.

I think that the OC Choppers move their HT motors over to clear the fat tires so there's precedent.

Alright. I was saving that for the last option because now i have to unhook everything! But i have to do what i have to do. Thanks for your help!

 

[Andrew735]

im not even sure if i can move it over. The supports that mount to the frame that hold up the bracket that has the motor attached to it have a thickness greater than the distance i need to move the motor over to make the sprockets allign... Does anyone have a Schwinn Jaguar with this grubee 49 cc 4-stroke that can help me?! i am out of ideas...