raw motorbike easy auto chain tentioner and expansion chamber exhaust

[joey d]

I have just done 2 new mods to my motorbike but I haven,t been able to test them yet. just wanted to see what you guys thought. Now I have to fix a major gas tank leak or finish aluminum tank. I am waiting for my aluminum brazing rods to show up. I got e expansion chamber on ebay for 30 including shipping and jb welded the copper pipe fittings together. put the pipe pretty much the only place it would fit. then then I attached it to the frame with 2 hose clamps. the heat guards was something I found in the shop. It had little spikes on it that I snapped off with some pliers.
The chain tensioner was just the stock one with a piece of flat stock bolted to it. I drilled a couple holes drilled in it got a spring at the hardware store and attached it to the frame with some bailing wire. let me know what you think. thanks Joey D

 

[tacoshell4]

does it run good?

 

[MikeJ]

Joey -

I like that chain tensioner idea. I will use that same basic setup for a pending build I will take on soon.

The JB Weld joints... Keep an eye on them. I have no knowledge that anyone every used JB Weld in an exhaust system that close to the engine. JB Weld is a two-part plastic resin, not true metal. My concern is that the joints will fail because they melted. I suggest you fasten the back end of your single-length exhaust pipe with some kind of safety wiring such that if the copper sections fall to the ground, the remaining unit does not fall backward, whip around, and jam the output pipe into your spokes. Your day will begin very badly after that one-millisecond turn for the worst.

Keep us posted how well that JB Weld works for you.

Mike

 

[retromike3]

expansion pipe

Do you get any problems with the pipe that close to your leg?

Mine goes under my B.B.


Mike Frye the bike guy

 

[MikeJ]

Joey -

Another suggestion.... Take a test joint of copper segments and the JB Weld and put them together. Then take a propane torch (or maybe borrow one) and heat the joint. See how much heat it takes to make the joint fail. Exhaust under severe stress like hill climbing has been documented on this forum to heat steel exhaust pipe to cherry red; still, the true welded joint did not fail.

I once made an exhaust pipe out of copper and 350 degree solder for a .40 cid model airplane engine. After 30 seconds of running, the whole good-looking assembly just melted into separate parts. I suspect JB Weld will do the same.

Mike

 

[joey d]

jb weld failed

I was thinking about trying high temp silicone for sealing fire places or I'll just weld up a good steel exhaust. I just liked the idea of all these premade angled pipe fittings some times the easy way isn't that easy.

 

[joey d]

I put a little heat shield on the pipe to keep it from burning my leg and haven't even felt any warmth after a 40 mile ride. pretty much put the pipe the only place I could make this one fit. I tried holding it up to the bike in every way possible and this was the only place it fit. I did seem to loose some low end torque from stock. I learned this while riding with a friend who has the same engine. lost a lot of hill climbing power but on flat to slight down hills I am cruising past him at about 38mph give or take. My friend has a speedo and his bike tops out at 32 mph stock. It was his estimate that I was hitting 38mph.

The auto chain tensioner made the ride so much smoother. also I suggest everyone do this Cause its cheap and easy and also takes out any chain slap. I am no longer getting chain rub on my tire and don't have to adjust my chain any more

 

[Mountainman]

a little bailing wire or duck tape to fill the gap

joey d

I agree with Mike
as much as I love JB Weld -- been using it for over 40 years now
don't think that you have a winner with that one -- a little too much heat there

regarding your chain tensioner -- should be fine
noTHING like a little bailing wire or duck tape to fill the gap

have fun as you ride that THING

 

[joey d]

I try to be about simplicity with my building I care a lot less about form then function. rat bike. You got the one of guy that gets the expensive bike and has a stock engine on it and then brags about how his bike is always gona be cooler then yours. (my friend). (Then me) with the $30 beater bike and all the free/under $25 minimalist upgrades I have time to do plus some I dont have time for. I love it

 

[professor]

Silver solder might work on your pipes. You would need to remove all the epoxy.