Unable to mount rear sprocket

[molash]

Hello all,
My friend and i want to build a motorized bike, this will be our first build. We got a nice bike to mount the motor to ,however we are unsure if the rear sprocket can be mounted along side the rear disc brake as there seems to be very little clearance, keep in mind that the motor has not arrived yet we are just speculating at this point. I will attach photos. We have considered other drivetrain options like either having output on the right side of the bike then connecting the output chain to the crankset directly or getting rid of the disk brake and somehow mounting the sprocket in its place and then just using regular brakes. Please advise.
The bike is a giant roam
Thanks

 

[DAMIEN1307]

If those are quick release levers on those wheels get rid of them and use real nuts with lock washers on them...Quick release wheels will never last on motorised bikes and is a major accident looking for a place to happen.

If that is a steel frame bicycle, NOT ALUMINUM, you will be able to stretch the rear portion of the frame to accomodate the rear wheel along with sprocket and disk brake rotor the same way that I did on my bike.

If it is aluminum, DON'T try to stretch it, the frame will crack and break on you.

Aluminum frame bikes are NOT recommended for motorised bicycle builds as they are not as forgiving as steel frame bikes...Aluminum WILL stress crack and break as they do not take kindly to the vibrations and speeds of motorised bicycles.

My bike was not disk brake ready with its own brackets welded on the frame like yours...I had to make my own adapters to put disk brakes on mine.

Here are the instructions below along with pics of my bike showing it can be done.

I don't recommend this method on an aluminum frame because it would probably crack and break, but this is what i did on my Steel Frame Hyper Beach Cruiser to accomodate the rear sprocket and disk to fit within the dropouts and frame.

On my bike, (steel frame ONLY), i had to "stretch" the rear forks apart by hand, about 1/2 an inch to put the rear wheel with sprocket/rotor attached, and then use a spare 15MM axle nut on the sprocket/rotor inside of the drop down, threaded to the axle with blue locktite, to maintain that amount of "stretch" to accommodate the amount of of clearance space the rotor needs so as not to be pressed against the frame.

It helps to have a buddy with a strong pair of hands to help in this proceedure like I did...lol.

​

 

[DAMIEN1307]

Also, what is the mm height of your rear disk rotor...160mm, 180mm or 203mm...The reason I ask is because of what size sprocket is going to be able to fit back there that will also allow for the disk caliper enough clearance in order to fit...In my case, it is a 36 tooth sprocket with a 203mm rear disk rotor...The caliper just barely has enough clearence, so make sure you have done your homework and your maths measurements properly.

You can see just how close the brake caliper is to the moving chain on the 36 tooth sprocket.

 

[GW's Motorized]

It looks to me like you have enough room for a sprocket. As Damien said, get rid of that wheel set and find some that aren't quick release. If you want a kick a$$ set of wheels get some mag wheels.

 

[Whitewill1412]

Welcome to the forum. There is always a way. You just have to find it. This is a fun hobby. Welcome to the madness

 

[GW's Motorized]

Yes, welcome. Which kit did you order?

 

[DAMIEN1307]

Yes, welcome. Which kit did you order?

They are in the northern suburb's of London, England so what is available for motorised kits over there are somewhat limited as to what we are used to here in the US or Canada.

Especially since our motorised bikes are not even street legal in the UK or most of Europe either.

 

[GW's Motorized]

Ahhh, I a. Still curious what kit was ordered.

 

[Risk Man]

Hello all,
My friend and i want to build a motorized bike, this will be our first build. We got a nice bike to mount the motor to ,however we are unsure if the rear sprocket can be mounted along side the rear disc brake as there seems to be very little clearance, keep in mind that the motor has not arrived yet we are just speculating at this point. I will attach photos. We have considered other drivetrain options like either having output on the right side of the bike then connecting the output chain to the crankset directly or getting rid of the disk brake and somehow mounting the sprocket in its place and then just using regular brakes. Please advise.
The bike is a giant roam
Thanks
View attachment 192626View attachment 192627View attachment 192628

check with your local bike shop to see if they can replace the skewer axle. with conventional threaded axle. If so, you may well be able to use these wheels with the proper adapter to mount the sprocket (made for the adapter) and the brake disk. `

 

[GW's Motorized]

check with your local bike shop to see if they can replace the skewer axle. with conventional threaded axle. If so, you may well be able to use these wheels with the proper adapter to mount the sprocket (made for the adapter) and the brake disk. `

I forget bike shops exist, I have to do all my mods with what I can get at the hardware store