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breaking in engine

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by Noel, Nov 26, 2004.

  1. My mannual says that during the break in period of 1000 kilometers that you should VARY SPEED - 'the engine speed should be varied and not held at a constant speed.
    Does this mean - don't stay at the same speed for more than, say, 5 seconds or - does this mean every 5 minutes change your speed?
    (the manual also says avoid constant low speed) does this mean that constant high speed is okay and how does this relate to varying the speed?

  2. Do a search as this has been covered extensively I think there is also something in articles so check as these are usually well worth the read!
  3. I was told vary things every couple of minutes and it only needs to be a few km/h or just go up and down the gears so the RPMs change which is the key rather than the actual change in speed.
  4. I heard it's pretty much irrelevant these days (esp with Jap engines), it's just some hang-over from the 'good old days' of engineering intolerance's (big word for this early in the day).

    As long as you don't red line the sucker before the first service you should be fine :)
  5. thrash the thing from the moment you get on it, chainge oil every 50 - 100 kms (cheapo mineral will do) but thrash it hard in every gear.

    if you put it against the same model bike that was run in the other way on a dyno it WILL make more hp.

    all this stuff about running engines in is crap, if you dont thrash it you wont hone the barrels correctly and your piston rings wont seat properly.

    let me reiterate it

  6. Engine run in periods are to allow the heating cycles of the engine to harden the components and to seat all the moving parts.
    This requires varying forces (acceleration and deceleration through the engine).
    General riding a bike normally will accomplish this fine, but long rides at constant speeds doesn't give this variation. Doing long rides at constant speeds just means your engine wont bed in properly for a longer period, hence you will need to extend your run in period. It should not cause any damage given that most rides are relatively short compared to what some people do in the cages (several hours at contant speed!). 10-15 minutes at one speed should not be any cause for concern.

    As the engine is tight when new, thrashing the engine will cause excesive heat generation and potential for premature engine wear, or at worst seizure (although this would be unlikely in all but extreme cases). This is the main reason for quoted run in periods - reduce the risk of catastrophic engine failure when you finally push it hard.

    All new bikes should be able to handle brief bursts to the redline from new, just don't run at sustained revs if you value the engine.
    Constant low speed is for similar reasons - for cooling when at low speeds causes heat build up.

    Enjoy your riding!
  7. I'm currently running in my new bike, and having lots of fun doing it :D

    Just ride it sensibly and you should be fine. Don't overheat the engine by constant full throttle acceleration, stick to between 1/2 to 3/4 of redline maximum for longegivity of your engine.

    Probably most important of all DO NOT run the engine at constant speeds for extended periods (say more than 5 mins) it will glaze? the cylinders. Lots of acceleration and deceleration cycles is good for them.

  8. Vary the speed. I agree, don't sit at one rpm.

    I would also take it to red line a few times during the run in period (later rather then soner). This will break any "glaze" that has developed in the bore.

    Also, how long before the first service? I would advise doing the first oil change a 500 km. Replace it with a running-in oil and then a normal oil at 1500km (if thats the first service).
  9. All good advice thankyou.
    umm, I don't have a redline gauge (tachometer). I've got a single cylinder 650cc. How do I know when I'm in the red zone.