Here's yet another question for the expierinced MBers

[Kpi890]

View attachment 81747 View attachment 81745 View attachment 81746 I seen earlier in this post I listed a video from MBRebel.com, that’s where I purchased the top hat. Here’s a couple pics of my MB. Hope that helps!

Wow man I love that build! Thanks for the pics, and what method did you use for the front and back engine mounts to the frame? It’s hard to tell in the photo but I know the front tube on the bike is rectangular so I’m just making sure I’ll have what I need to get the build done when it arrives?

 

[Carl Walichnowski]

Wow man I love that build! Thanks for the pics, and what method did you use for the front and back engine mounts to the frame? It’s hard to tell in the photo but I know the front tube on the bike is rectangular so I’m just making sure I’ll have what I need to get the build done when it arrives?

Oh I forgot to mention in order for the chain to align I had to go with that top hat but that gave me clearance issues with my rear disc brake caliber. I previously just said to hell with the rear disc brakes but we’re currently trying to come up with a fix for the issue so I can use the rear disc brakes. Any suggestions?

 

[Frankenstein]

Oh I forgot to mention in order for the chain to align I had to go with that top hat but that gave me clearance issues with my rear disc brake caliber. I previously just said to hell with the rear disc brakes but we’re currently trying to come up with a fix for the issue so I can use the rear disc brakes. Any suggestions?

How exactly is it interfering? The caliper too close to the sprocket?

 

[Frankenstein]

How exactly is it interfering? The caliper too close to the sprocket?

Hmm, thinking about it that front disk brake looks stock, probably 160mm since it's popular and cheap, and about the same size as your rear sprocket. They have really large rotors available, if something like a 250 (or whatever is 'the standard' for huge rotors) was installed that could give you a disk that sits almost 2 inches above the chain and sprocket, a rotor and caliper on the appropriate bridge may clear that issue, measure twice and buy once.

Are rim brakes off limits on your mag rims?

 

[Stoneman]

Isn’t this what you want or are we way past this point ?

The disc bracket was not used with this sprocket

 

[Carl Walichnowski]

Hmm, thinking about it that front disk brake looks stock, probably 160mm since it's popular and cheap, and about the same size as your rear sprocket. They have really large rotors available, if something like a 250 (or whatever is 'the standard' for huge rotors) was installed that could give you a disk that sits almost 2 inches above the chain and sprocket, a rotor and caliper on the appropriate bridge may clear that issue, measure twice and buy once.

Are rim brakes off limits on your mag rims?

Yea the issue is the caliper is to close to the sprocket. I was considering getting a smaller sprocket as an easy fix but not sure if it'd work. Somebody said spacers but the clearance issue is about 1/2 ". I did see a video that showed the big rotors and that may be a fix if nothing else can work. Rim brakes aren't out of the question but I was hoping to make this work somehow before I bought additional parts.

 

[FurryOnTheInside]

Oh I forgot to mention in order for the chain to align I had to go with that top hat but that gave me clearance issues with my rear disc brake caliber. I previously just said to hell with the rear disc brakes but we’re currently trying to come up with a fix for the issue so I can use the rear disc brakes. Any suggestions?

What is the diameter of your rear sprocket, or rather the chain on the sprocket?
203mm rotors are commonly available and can be cheap. 220mm and 225mm are rarer and never cheap. 254mm exists but costs a fortune.
Are your calipers post mount and do they use a PM-IS adapter already?
You can buy adapters to move the caliper out to the new rotor diameter, but they won't move it outboard to account for the thickness of the top hat (6mm?), so you'll have to buy some flat 6061 aluminium plate online and then shape it and drill it to fit between the frame and the existing 160 PM-IS adapter. If the outside of your dropout is flat you can bolt the plate onto the outside.

You'll need a (front specific) 160-203 adapter for the front too so that it doesn't look wrong lol.

And don't forget to check that the large diameter rotor will clear the frame stays when it's bolted onto the outside of the top hat!

 

[Carl Walichnowski]

What is the diameter of your rear sprocket, or rather the chain on the sprocket?
203mm rotors are commonly available and can be cheap. 220mm and 225mm are rarer and never cheap. 254mm exists but costs a fortune.
Are your calipers post mount and do they use a PM-IS adapter already?
You can buy adapters to move the caliper out to the new rotor diameter, but they won't move it outboard to account for the thickness of the top hat (6mm?), so you'll have to buy some flat 6061 aluminium plate online and then shape it and drill it to fit between the frame and the existing 160 PM-IS adapter. If the outside of your dropout is flat you can bolt the plate onto the outside.

You'll need a (front specific) 160-203 adapter for the front too so that it doesn't look wrong lol.

And don't forget to check that the large diameter rotor will clear the frame stays when it's bolted onto the outside of the top hat!

Unfortunately I don't know what size the diameter is of the rear sprocket and the bike is in a shop getting worked on due to my lack of experience. Honestly I just love riding the MB and pay someone else to do the work but I'm learning as I go. I'll try and get those #'s for ya ASAP.

 

[Frankenstein]

I sometimes wonder... What if a large steel disk was bought, and then simply machined and/or drilled to be a disk brake rotor. I've seen minibikes and motorcycles with what is almost a solid rotor, and come to think of it so is the case for almost every freaking vehicle known to man. What's it to just mimic the mimics' mimics?

I'd bet the little bracket that mounts the caliper the appropriate distance away isn't all that expensive, and I'd be crazy enough to try working with a miter saw blade as a good reliable base, about the right thickness too. Since I've never seen one shatter I'd feel actually pretty safe using it. Options options...

 

[FurryOnTheInside]

I sometimes wonder... What if a large steel disk was bought, and then simply machined and/or drilled to be a disk brake rotor. I've seen minibikes and motorcycles with what is almost a solid rotor, and come to think of it so is the case for almost every freaking vehicle known to man. What's it to just mimic the mimics' mimics?

I'd bet the little bracket that mounts the caliper the appropriate distance away isn't all that expensive, and I'd be crazy enough to try working with a miter saw blade as a good reliable base, about the right thickness too. Since I've never seen one shatter I'd feel actually pretty safe using it. Options options...

I think there's a limit to the diameter you want to go to with a single piece thin (2mm iirc) steel disc just due to their tendency to warp when heated around the edge. 203mm rotors can be quite cheap.