My bike just about dialed in.

My first post. There it is, my first bike. Hiland MTB 66cc motor cleaned up internals, port matched, NGK plug, extractor exhaust, HP carb, 52 tooth rear sprocket and modified stock muffler. Stock internals and head.
Took a long time to make this happen, watched a lot of youtube and read the forums. This one is the best by far.
A few details, the extractor on it's own was way too loud so I put the stock muffler on which killed the power so I made it into a glass pack by gutting the internals, drilling several more holes in the pipe, wrapped it loosely with expanded screen and filled the cavity with fibre glass. Works great not too loud.
The stock rear sprocket was drilled to mount on the disc brake hub but found it way too fast and had no hill climbing power so I bolted the 52 to the 44.

 

[GW's Motorized]

Free flex is actually desirable when you are going faster on a bicycle. It will absorb bumps better. This is one of the reasons an aluminum frame cracks with a motor

 

[gearhead437]

I asked about the bike frame material as steel is considered less brittle and more flexible than aluminum. I was told that by a bike shop supervisor. On the other hand, it can be difficult finding a quality built steel frame bike, so I don't blame anybody for choosing an aluminum frame simply from an initial build quality perspective-Gearhead437

 

[DAMIEN1307]

I was told that by a bike shop supervisor.

Did you also specifically tell this bike shop supervisor that this aluminum frame would have to be able to withstand a motor being put on it with the usual vibration to be expected and that this aluminum frame bike would be going three to four times faster than pedal pushing power???

 

[Wrench]

IMO steel frame is always better for a M/B,
Crack's in a steel frame develops over time and gives the rider warning because their not catastrophic and easily repaired by welding
Cracks in aluminum frame are sudden and catastrophic and not easily repaired by welding

 

[robe]

Here are a few pictures of my low budget muffler mod.

Also put the BoFeng carb on and went for a long ride, I think i will leave the muffler as it is, everything is working better than it ever has except the idle is a bit inconsistent still. Maybe the dreaded air leak somewhere.

Had my first catastrophic failure on the last big hill before home. The disc brake mount sheared off from the rest of the hub leaving the drive sprocket free wheeling. I thought the clutch came apart but no such luck. I would like to keep the wheels, they are double walled and are still true but use 32 spokes. All the steel replacement hubs I can find are 36. I could replace what I had but seems to be a weak point and all the replacements are quick release.

 

[GW's Motorized]

Here are a few pictures of my low budget muffler mod.

Also put the BoFeng carb on and went for a long ride, I think i will leave the muffler as it is, everything is working better than it ever has except the idle is a bit inconsistent still. Maybe the dreaded air leak somewhere.

Had my first catastrophic failure on the last big hill before home. The disc brake mount sheared off from the rest of the hub leaving the drive sprocket free wheeling. I thought the clutch came apart but no such luck. I would like to keep the wheels, they are double walled and are still true but use 32 spokes. All the steel replacement hubs I can find are 36. I could replace what I had but seems to be a weak point and all the replacements are quick release.

Is that a moded stock muffler?

 

[robe]

Is that a molded stock muffler?

Yes it is. I explained a bit about it in, Expansion chamber too loud. Have to say for a low budget hack job it works really well. The stock mufflers really vary between them. The last one I took apart had very few holes in the first pipe with the threaded bit welded on. This one has 12 - 1/4 holes a square area of only .54 inch, I didn't think it would be enough but it sure ran great today. I don't think I will change that. For once I am happy the first time at it.

 

[GW's Motorized]

Yes it is. I explained a bit about it in, Expansion chamber too loud. Have to say for a low budget hack job it works really well. The stock mufflers really vary between them. The last one I took apart had very few holes in the first pipe with the threaded bit welded on. This one has 12 - 1/4 holes a square area of only .54 inch, I didn't think it would be enough but it sure ran great today. I don't think I will change that. For once I am happy the first time at it.

I'd like to know how it sounds.

 

[Chainlube]

Here are a few pictures of my low budget muffler mod.

Also put the BoFeng carb on and went for a long ride, I think i will leave the muffler as it is, everything is working better than it ever has except the idle is a bit inconsistent still. Maybe the dreaded air leak somewhere.

Had my first catastrophic failure on the last big hill before home. The disc brake mount sheared off from the rest of the hub leaving the drive sprocket free wheeling. I thought the clutch came apart but no such luck. I would like to keep the wheels, they are double walled and are still true but use 32 spokes. All the steel replacement hubs I can find are 36. I could replace what I had but seems to be a weak point and all the replacements are quick release.

If you really pack the insulation in there hard, it won't blow out as easy and keep it quiet. I did that on my MB, but I put a ton of little holes in the end of the stinger pipe before I jammed in the insulation.

 

[robe]

If you really pack the insulation in there hard, it won't blow out as easy and keep it quiet. I did that on my MB, but I put a ton of little holes in the end of the stinger pipe before I jammed in the insulation.

Thanks. My new muffler hack seems to work really well, I'm keeping this arrangement for a while. Somehow it added just the right amount of back pressure and the power really increased.

I've been looking at what to do to fix my rear wheel. CDH will free ship me a set of ten spoke mags but then I would have to set up a disc for the rear and with my 52 sprocket it would be a problem.
So far I'm going to get a new hub and transfer my old stuff to the new hub. Wheel lacing you tube to the rescue.

The rains are returning with a vengeance, so everyday riding is coming to an end here.