What kind of motor mount do you use on a 2" down tube?

[Redneck in China]

Thanks Bolts Missing, that looks interesting. Is there any particular reason for using that arrangement as opposed to a muffler clamp (other than looks maybe)? I lean more toward a clamp for an aluminum frame since it would spread out the clamping force around fairly evenly the entire circumference as opposed to squishing it from the top and bottom. Is your frame aluminum or steel? What dia.?

I don't know how stout this thing should be. It's just a puny engine, but the frame is aluminum so I want to be really kind to it as much as possible.

Mark

 

[BoltsMissing]

Is there any particular reason for using that arrangement as opposed to a muffler clamp (other than looks maybe)?

Muffler clamps are for mufflers.

The other reason is, the botton plate covers more area than a clamp's U-bolt don't you think ?

 

[Ghost0]

We have found the muffler style clamp to work very well as a frame mount. We use it both in our Shift Kit rear motor mount and our Universal Front Mount and have had no problems with them in testing or reports back from the hundreds of customers using them. Agreed they are not as pretty as a machined billet aluminum clamp, but one of those would raise the cost way above the average persons comfort level. We do recommend in the instructions for both kits that when using an aluminum frame it is wise to use the stock engine strap to offer added support to the u bolt. As was previously mentioned we are working on a mount to go from the 1.5 to 2 inch tubes. Our current one will only work for the 1.125 to 1.5 range.

 

[will_start]

Hey Ghost,

I looked at some muffler clamps at Auto-One.
They only cost about $4 AU.

The question I have is how to link the Engine to the muffler clamp ??

 

[BoltsMissing]

Don't mean to hi-jack ya question Will-Start,
This method is being done on my own personal use build, a 26" Huffy.
Uses 2 HT C-Clamps, and leather between the C-Clamp and engine case.
In the pic it ain't tightened up yet, ongoing buid when time permits.
I think Zbox sells C-Clamps cheaper than muffler U-bolts.
Not all HT C-Clamps will fit, some need to be milled out a fraction.
If too wide a tube, then yes the other easy option is to use plates and muffler U-bolts.
Some usef muffler U-bolts is last resort, others it's first option.
So far HT parts can be used in most mountings with some improvising.
I suppose once it's alll fitted nicely and square you can remove the burrs and rough edges and polish the alloy HT C-Clamp accordingly.
Note the plate on the back of the far rear HT C-Clamp, important !

 

[Redneck in China]

Quote:
Is there any particular reason for using that arrangement as opposed to a muffler clamp (other than looks maybe)?
Muffler clamps are for mufflers.

The other reason is, the botton plate covers more area than a clamp's U-bolt don't you think ?

Response:
Muffler clamps look the way they do because the design is an effective way to get a tight even grip on a round surface without distorting the round shape through pinching. This is even more important on a bike frame because the metal is aluminum vs. steel and is a structural part whereas an exhaust pipe is not. Muffler clamps may be for mufflers, but it makes sense to use them since they are designed to do what we want them to do. The only question for me really is am I going to an unnecessary extreme? Do people who use 2" lightweight aluminum frames and drill holes or use other types of mounting brackets experience failures? I imagine failures would be more rare with steel, but I'm talking specifically about 2" aluminum. I've never had a frame crack and break, but I imagine it involves the rider going butt over tea kettle which would be un-fun. I wanna avoid that. As long as it keeps me from busting my precious butt I don't really care what it looks like.

Thanks for all the feedback!

Mark

 

[Redneck in China]

A possible solution to all of this?

Why don't the Chinese engine manufacturers make specific adapter kits for their engines for specific frame tube shapes and diameters? There aren't that many and it wouldn't be that hard. It would really add a lot to the overall product I think.

Here in China, believe it or not, it looks like very few bikes will take one of these engines as an easy bolt-on. A lot of frames are too short and most others have big down tubes or tubes with weird shapes. One of the only kind of bikes here that the motors WILL fit is the "are bah chuh" (literally "two eight vehicle") like the one in the photo I tried to attach (if it worked). These things are ancient in design with crappy brakes. 10 years ago it was all you could buy here. It looks like they designed the motor to be an easy bolt-on for this bike and haven't given a lot of thought as to how their motors can work on a wide variety of bike types. Can you vendors out there suggest that the Chinese get with the program and give us kits that bolt on, right out of the box (through adapters, different size mounts, etc.) to modern bikes? I noticed that when you buy a shift kit from SBP they want to know your seat post tube dia. Why? because IT MATTERS and they give you a kit to fit YOUR bike. COOL! Why cant the engine manufacturers do the same?

I'm trying to find a used bike where I live in China and I swear that these kits will probably bolt-on without mods to less than 10% of the multi-speed bikes around here and this is IN CHINA! If they would give us a complete package to start with we wouldn't have to go through all this. Ok. I'm done ranting now.

 

[Junster]

Here's an engine mount with some serious wow factor.

http://home.roadrunner.com/~bikeparts/ENGINE MOUNT.htm

 

[BoltsMissing]

Junster Here's an engine mount with some serious wow factor.

http://web.tampabay.rr.com/bikeparts/ENGINE MOUNT.htm

yep, that's the idea, a touch of Class.

How much for a cradle/mount of that particular type ?

 

[Junster]

It's the only thing on his site he doesn't have a price on. So I'm not sure. I bought one of his copper exhaust gaskets. He was very quick to ship. He also has the nicest rear sprocket mounts I've seen.