3rd build

Discussion in 'Photos & Bicycle Builds' started by wildemere, Mar 4, 2008.

  1. wildemere

    wildemere Member

    This is my latest effort

    Features include home made 40 tooth rear sprocket, a BMX chain, no tensioner, and high pressure tires.

    The tires are rated for 90psi, running them at 75psi.

    The 40 tooth sprocket used to be on the chain ring!

    Its just a cheap old mountain bike fitted with 27" wheels.

    vmax as of yesterday was 35 mph

    Would probably go near 40 but I fear a meltdown, seizure or explosion.

    A lockup at 40 would not be pretty.

    Attached Files:

  2. Hollywood

    Hollywood Guest

    Nice build mate!!!
  3. alesterfeind

    alesterfeind Guest

    Very nice Wildemere. How do you get the BMX chain to fit over the drive sprocket on the engine? Did you change it out?
  4. wildemere

    wildemere Member

    I just ground it down a bit
  5. azbill

    azbill Active Member

  6. hellbilly

    hellbilly Guest

    Looks like it's "Built for Speed". Nice job. I too just ground the black off the teeth of the drive sprocket in order to use the KMC510 BMX chain, then a nice smear of grease to help break in.:smile:
  7. graucho

    graucho Active Member

    Looks lean, yet mean. Looks like the engine mounted perfect with your frame/tube diameter.
  8. Dude I need some more info on that homemade 40 tooth rear sprocket. It looks like you got a plate going on there with the extra bolts.
    Nice bike! I bet that extra inch on the wheels (27 as opposed to 26) makes a noticable difference in speed.
  9. wildemere

    wildemere Member

    I used the 40 tooth "low" gear from the front chain ring. It had 5 holes in it. I then made a carrier out of 5mm alloy plate using the old happy time part for a drilling template.

    I then used a jigsaw (outer circle) and a hole saw (inner circle) to finish off the part. It has been reliable so far.

    Its just a dough nut of metal with lots of holes in it.
  10. very nice build.