4-stroke Grubee Sprocket Alignment

Discussion in 'Frame Mounted Engines' started by Andrew735, Mar 15, 2008.

  1. Andrew735

    Andrew735 Member

    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?
     

  2. mickey

    mickey Guest

    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?
     
  3. Andrew735

    Andrew735 Member

    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?
     
  4. mickey

    mickey Guest

    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?
     
  5. Andrew735

    Andrew735 Member

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

    mickey Guest

    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
     
    Last edited by a moderator: Mar 15, 2008
  7. Andrew735

    Andrew735 Member

    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.
     
  8. mickey

    mickey Guest

    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. :grin:

    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.
     
    Last edited by a moderator: Mar 15, 2008
  9. Andrew735

    Andrew735 Member

    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!
     
  10. Andrew735

    Andrew735 Member

    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...
     
  11. mickey

    mickey Guest

    What about making the hole in the sprocket bigger so it can move inward on the spokes? Depending on the dish of the wheel, you probably won't get a 1/2 inch like you need, but you would get something. At least 1/4.
     
  12. nsideus

    nsideus Guest

    I have/had the same problem on a Schwinn Point beach. When I sat the engine in place with it moved clear to the left the chain would still not clear the down post. I modified the mounting slots to slide the motor into position. I also needed to machine the aluminum brackets for the bolt heads. I made new motor mounts out of angle iron since the adjustments pushed the engine too far over to give stable mount. There are a few more minor adjustments that need to be made. If you come up with a better solution I'd like to hear it.
     
  13. Andrew735

    Andrew735 Member

    Well that sounds like the same problem that im having. All i need is to move it over a good centimeter and it will line up the sprockets. If i flip the rear sprocket over then it will rub the tire. I kinda understand what you did to make yours fit. Why did you need to make new motor mounts and what did you use for that?
     
  14. nsideus

    nsideus Guest

    Sorry for not getting back sooner. I abandoned the new brackets and was able to get alignment with just widening the mounting slots to the left. The rear sprocket is mounted with the teeth out. I had to trim the rear fender and add a couple of washers to the left of the axel to give chain clearance past the frame.
     

    Attached Files:

    Last edited by a moderator: Mar 22, 2008
  15. mickey

    mickey Guest

    So its good now?
     
  16. Andrew735

    Andrew735 Member

    its not quite good yet. We just drilled straight through the aluminum blocks and through the steel mounting plate. this would have worked great, but it butted the other two bolts against the side of the blocks. im still not sure what to do.
     
  17. ocscully

    ocscully Member

    How about mounting the motor to a seperate flat plate and then secure this new assembly to the Grubee Mount. This should allow you to get more than enough room for the proper chain alignment.

    ocscully
     
  18. HoughMade

    HoughMade Guest

    This will not get you 1 cm, but it's something.

    You will notice that the aluminum blocks are slightly narrower than the steel mounting plate, that is, there is some play. When I needed about 3/16 of an inch, I loosenned all the bolts that mount the plate to the aluminum blocks, then I tighten down the ones on the right side as far as they will go..tight- keep in mind I replaced the woefully soft blots with good quality. Only then did I snug down the bolts under the gearbox. What this does is allow the engine plate to sit as far to the left as possible given that it is wider than the aluminum plates. I still have more than 1/4" clearance from the pedal on that side.
     
  19. MasterLink

    MasterLink Member

    i have the jaguar and i didnt have line up issues few thing i can say is my back disk is flipped inward so looks as there is a ridge outside the sprocket 2 is my mount i flipped my motor upside down and moved all the way left tighting the 4 bolts the back alum. block seemed different to me the 2 pieces (i dont realy remeber have a look .. ..
    3 mount that back block set it on you chain gard level it tightin it down let it move all the way back i used the last set off holes ..4 let the front float put eng. in frame bringing the front mount into place leveeing it off here.... i used the first set of holes if that all dosent line up 5 you sprocket is set up wrong with the washers i have 1inch to 1.2 inch clearance with my chain on the back wheel ohh i just got done putting helicoils in all the alum. and got number 5 1/4 harden steal bolts for everything thats a big upgrade auto parts store has 1/4 inch coils and ask him for the right size bit then just drill them out at home then go to a gas station to put them in saves a lotsssss of money then you dont have to pay for the kit this is so clear in my head because i have been working on this last 2 days geting the mount to stay put ...
    ohh then i pulled a few links out of the chain then install the chain tension close as you can to the top chain

    jaguar and point beach are the same bike frame
     
    Last edited: May 22, 2008
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