Gt80 junk?

I have been considering putting on am expansion cahmber,from BikeBerry.
NO MUFFLER NO SILENCER. My only concerned is,,,,,,,,,no silencer/Muffler, now this because it's high performance. O d
DO-NOT!!!!!WANT SOMETHING SPITTING OIL ON ME OR MY FRAME/MAGS! .......DOES AMYONE HAVE ANY EXPERIENCE with these.l?

I do Bob, switch to a good quality synthetic and use less than 32:1 and you will not have oil spit out the pipe.
32:1 is about the border line, I still get a tiny bit of oil. None at 40:1.

I tried a similar pipe from www.motorizedbicycle.ca/
full


I would not call it a "tuned pipe" or "expansion chamber" in the true sense of the name.
Its power band was at mid to low rpm (better than stock) and it was actually noisier than stock.

Steve
 
Thanks a bunch Steve. I was thinking of ordering that exact pipe? But, I got nervous when I seen that "BIG NUT" rite where the where the engine is. I guess it's no problem though.
I was also gonna GET a Huffydavidson CDI/ignition set Up. But you can't take the plug wire out and replace it with an automotive plug wire so I don't need to "TAKE MY NIPPLES OFF!" I LIKE NIPPLES!!!
;-) that was the only deal breaker and jag's is just a bit too much $$$$$$ any suggestions? I'm also gonna port intake and output sooner or later hopefully sooner than later.
Thanks
Bob.
 
I wanna have enough speed and confidence so when I go visit my daughter 20. Miles give or take, I can do it safely and be able to keep up when I need to I'm living in the burbs caring for handicaped family member rite now in the western subrubs. She's rite on the edge of the CITY. All my bearings are new I just need new retailers Wichita I got a line on and its all new accept the frame. AND THAT DIAMOND BACK IS SOLID!!!
 
Your rite Jag, thanks for the good info. I will and have done all those things. However I did put a single inertube wrap around the seatpost when I mounted my Wichita is all but gone accept a little residue on the inside of the frame tube after taking IT out, I fihured WTH? Its not gonna hurt its such a minute amount of rubber. More like a stain. So thanks. A bunch.
Bob
 
Bob, I did some stock pipe testing this afternoon. This is a mostly copy and paste from another post:

I have a recently abandoned runway in my backyard for testing.
Level but strong winds, saw speeds of as low as 40 kph against the wind and then as high as 58 with it.
48cc (stock cylinder, converted back to single speed 56T) and 66cc (44t stock cylinder), both with modded heads.
48cc is in a lightweight 10spd frame (with shifter frame still in place), 66cc in a heavy MTB and big tires.

Upwind/downwind, 48cc/66cc. speeds in Kph
stock pipe= 44/52, 44/57,
portmatched pipe= 46/52, 46/58
Straight pipe= 40/42, 42/44
Stock portmatched pipe, baffle removed= 42/48, 42/50

Steve
 
thank you for sharing, i did some plug testing & short list ,,,E3-22 3rd/ NGK B7HS 2ND/ BEST PLUG IN 1ST PLACE 100 degrees 90% plus humidity .NGK IRIDIUM BPR7HIX 5944. tires were sticking to the pavement.

thanks again

Bob
 
These engines are surprisingly reliable so long as 25:1 oil/fuel ratio is used, and there are no air leaks, and carburettor jetting is optimised, and they are not over revved.
It is much better to add aftermarket accessories that boost torque; enabling you to use lower rpm to make the same horsepower. The engine will be in a lower state of stress, and provide significantly greater reliability, with reduced vibration.

Excessively high compression cylinder heads, as well as not having large cooling surface area tend to cause detonation issues, which damages connecting rod bearings.

My setup achieves exactly that. The top end is good for 2,500 miles, and the bottom end is good for 6,000 miles to "near failure" point.

 
These engines are surprisingly reliable so long as 25:1 oil/fuel ratio is used, and there are no air leaks, and carburettor jetting is optimised, and they are not over revved.
It is much better to add aftermarket accessories that boost torque; enabling you to use lower rpm to make the same horsepower. The engine will be in a lower state of stress, and provide significantly greater reliability, with reduced vibration.

Excessively high compression cylinder heads, as well as not having large cooling surface area tend to cause detonation issues, which damages connecting rod bearings.

My setup achieves exactly that. The top end is good for 2,500 miles, and the bottom end is good for 6,000 miles to "near failure" point.


Id think that low end torque would be harder on chains and the clutch.... It would also be harder to keep cool
 
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