Search results

  1. mobike91

    Square or round exhaust port?

    I'm thinking that the round shape would allow for more sound wave from a pipe to more effectively push the scavenge of the fuel mix back into the cylinder. Can't prove it, but in my mind it seems logical. Guess I'll have to build both and test ride the snot out of both lol
  2. mobike91

    kings motors gt 80

    I just read this long post. I like the reviews. Iv had my kings gt80 engine now for over a year. I ported the transfers going into the case, matched them at the jug, ported a huge window on the piston, made a light exhaust relief ramping on the piston, filed the end of the rings a smidge. Opened...
  3. mobike91

    Bicylce-Engines expansion chamber

    I would say no. They don't offer any power band in that design at all. The header port is nothing more than stock, the tune if it had one would be at a pretty low rpm.
  4. mobike91

    Hybrid cylinder engine options

    So Iv always wanted to build a hybrid cylinder engine out of our China girl bottom end and a jug and head from another bike or scooter. I remember reading years back about puch cylinders and heads being done and I saw a few videos on YouTube of them but never really dug in. I was looking up...
  5. mobike91

    Custom built x pipe

    So after I got all the pipe pieces figured out I strapped the pipe to the bike with zip ties to hold it in place while I busted out the welder to tack the thing in place. Now I don't have a mig but I do have a 30-275 amp arc welder that Iv built everything with so welds don't look beautiful by...
  6. mobike91

    Custom built x pipe

    At this point I had cut my hands a few times on sharp metal from sorta rushing the job from all the excitemement of finally building a good pipe to put on my MB lol. Iv always wanted to get creative and build one but hadn't had the motivation to do it or the idea storming in my head of how the...
  7. mobike91

    Custom built x pipe

    It only lets me upload 5 at a time......-.- and we continue
  8. mobike91

    Custom built x pipe

    First I started with a eyeball fit up. Kinda getting an idea of what I needed to do. Found that I needed to cut like 3"s off the header portion that mated up to the 125. I started cutting Sertain parts off that I thought I could use to make the pipe fit up. I was...
  9. mobike91

    Custom built x pipe

  10. mobike91

    Custom built x pipe

    So while I was at work last night digging around looking at just about every expansion pipe on eBay I could find, I found a style I thought would work good n saved them to my eBay. My dirtbike riding roommate had tossed a old ktm 125 pipe in my scrap pile a couple weeks ago. He said I could use...
  11. mobike91

    Does anyone know who builds custom exhausts?

    Got any pics of how you did it? I just saw some good ones on eBay
  12. mobike91

    Does anyone know who builds custom exhausts?

    Got pics of that? Sounds awesome.
  13. mobike91

    Bicylce-Engines expansion chamber

    Here's a wayyyy old video of it. You can see the pipe I built off of it lol https://youtu.be/iHjaTAYwB9o
  14. mobike91

    Bicylce-Engines expansion chamber

    I bought that pipe years ago when they called it the banana pipe. It didn't do much but sounded awesome. I ended up cutting the exhaust off at the end and building a full length pipe after it out the back of the bike. It looked awesome.
  15. mobike91

    Universal Expansion Chambers

    Bairdco could I PayPal you and have you ship me one to Oregon? I'd love to tinker with a better expansion chamber than I got. I also am hoping to make it out to Cali this year for some racing in October! If that's where your taking about lol.
  16. mobike91

    BBR F2 thrust exhaust - anyone tried/have this?

    How much does he charge for them? Yeah the pipe looks good but those style always offer the same set way back tune that doesn't seem to offer that much power really. I got a very similar pipe on my bike and it has no surprise powerband at all, and my motor is ported to **** so if it was gonna...
  17. mobike91

    New high comp head!

    Did the exhaust add any noticeable power improvements?
  18. mobike91

    Stock motor 38MPH

    After about the 15th engine destroying itself in another various way, I began to realize that these little engines were not meant to be primary transportation and a racecar lol. One must have both a put put bike and a experimental race bike to be satisfied in riding these. My favorite engine...
  19. mobike91

    High comp head.

    I wouldn't think so, but it will make your engine possibly ping or 4 stroke more on regular gas. You may need to move up to pure premium gas with this change in compression ratio.
  20. mobike91

    New high comp head!

    You should do a compression test and give us numbers on what you find for pressures, Iv been curious about that head for a while n wasn't sure if I should give it a shot or not. Also where did you get that pipe? I have one very similar to yours but it doesn't for my bike at all.