Break In Running in a new engine

Discussion in '2-Stroke Engines' started by atomichurley, Dec 13, 2010.

  1. atomichurley

    atomichurley Member

    Hey guys, i have ordered a rocksolid engines 70cc hp stage 2 engine kit it should be arriving in the next few days. after owning a 70cc engine from zbox and not running it in properly and having it seize i would like to know what the best way to run an engine things like (fuel oil ratio,1/4 1/2 and full throttle,max speed,running time and to leave idling or not)

    Heres the engine i have ordered:

    Heres the bike i'll be mounting it to

  2. motorpsycho

    motorpsycho Active Member

    well, they say to run a 20:1 gas-oil ratio in general for break in. (like 2-3 tanks full) this is not specific to any certain engine, i think it's just rule of thumb. They also say to limit your riding time to no more than 30 minutes at a time ketting the engine cool completey between rides. don't go over 1/2 throttle for the first tank and then gradually you can increase the throttle. This is just what i have read.
    when i broke in both of my engines i ran a 20:1 gas-oil ratio for 1-2 tanks, and then went to 32:1 on my 3rd tank. on my 3rd tank, i was going full throttle but not holding it wide open for a long time.
    you will get 2 different stories on break in. some guys will say to take it easy and do what i described above, other will say to run it full throttle right out of the box, and others will say to vary the rpm's from idle to full throttle as you ride.

    Normally with full race engines you can go full throttle on a fresh engine, but with these engines, i think it's best to go 20:1 for a few tanks and take it easy on the throttle for awhile. just baby it for the first couple of tanks, and then switch to 32:1 and start easing closer towards full throttle. The key tho, is to limit your ride time to 30 min, at a time and letting the engine cool completely before your next ride. this helps seat the rings by allowing the cylinder to fully expand and fully contract. This is based on my knowledge anyway.
    your new engine should come with some kind of instructions that will tell you how THEY want you to break it in.
    Samdallas214 likes this.
  3. joshua97

    joshua97 Member

    Th zbox website say less than 25 kph for 500 ks haha lol. i ran mine in for 260 ks that was 3.5 tanks for me ant 30kph, 3,200 ish later I'm up for new ring soo not bad
  4. Samdallas214

    Samdallas214 Member

    I own and ride a china girl 4 stroke but I have built 3, 2 stroke kits for others.
    All purchased all 3 at the same time from the same vendor.
    1 ran it full throttle right out of the box, 32-1 mixture, 2 other 2 used 25-1 mixture and keep it at 1/2 -3/4 throttle for the first 2 tanks.
    So far no difference all 3 runs about the same, all 3 now using 32-1 and mix
    all 3 max out at 25- 30 mph, but all 3 weight 200 + pounds riders
    hopes this helps