Honda Spree and Elite 50 Forums

I just install a 72cc corsa into my SYM motor. I was wondering if there's any methods when breaking in a new bore.

I was advise to start it up and let it run through five gas gas tanks before I even jump on and ride it. Lmk what best works for you guys? Any advice would be much appreciated.

Aloha, scoot809

Start the bike and idle it kinda of in a lower than normla idle and let it slowly rise to about 130*F, than kill the bike and let it cool all the way down. Then the next time go to 150, than cool down, 170, than to what ever is evens out to at idle in about 8 minutes then let completely cool down and check plug and adjust jets. First riding tank constantly change throttle position, its agervating but sitting in one spot will wear your rings odd and diminish life. Dont go over half theottle first tank, watch for air leaks. Air leaks are especcialy killer. I belive in the plenty of heat cycles, 1 nice smooth tank than ride it hard because if it is gonna break, its gonna break then. Just watch your temps and keep an eye for airleaks.

5 tanks is crazy, like jumps said, do heat cycles, i did 10 instead of only 5. Them half tank under half throttle never holding same position. My corsas took 5000 mi, and hard.

The trick with a proper break in is to advance a little more each time, start low or start in the mid section. Find what people idle the bike at and what people bring the bore up to at wot and do that at. Idle it up to half the idle than the idle than about 30 degree incrimants. Lightly ride the bike first few tanks, plenty of throttle blipping. High revs for very short times on about the 5th tank. If the bike stops heat spiking your good to go. This is my method...

everyone has different methods on how this is done. I keep it simple I heat cycle 10 times letting it get up to temp then shutting it down till its ambient temp. then I run the first tank constantly changing the throttle position but never really getting on it hard. then once I feel confident I start opening her up more and more till im sure my temps are where I want them to be. the key in my opinion is making sure you dont have any airleaks. I have done this with all my set ups and my current setup is running temps in the low to mid 300s. I have also known guys to just throw it together and go and not have any issues not that I recommend that but I have seen it done. I was always told the heat cycles help the rings seat and so thats why I do them. and for me its also a good time to work on the idle and get it dialed.

My big thing is ive been told getting the rings to seat is 50% heat cycles 50% down shifts and constant throttle movement. You want your rings to wear to every rpm range in your bore not to a set idle or what ever. I wouldnt even rev the bike till the 3rd heat cycle though. It will heat spike like a * if you do.

Thank you much for your guys input:

Update on my break in.

For about half of a tank I let it idle. After about an hour into it I noticed oil leak. I stopped that bike and proceded to look where it was coming from. The gasket for my exhaust was no good and needed to be replaced. After replacing the gaskets it never had the leaking issue.

At this time I made a choice to go and take a ride. Rode for about and hour or so/constantly changing throttle positions(1gastank).
While riding I didn't go above 25 Mphs and the bike temp never got hotter than 330. I'm on my second gas tank now and started to ride it much harder. For the first half of the tank, I was able to get my temp gage up to 420, constantly changing throttle positions. I'm going through the second half and really pushing it, I was able to get my temp gage read 460. I held it wide open for 5-10 secs quater/half throttled it for 2-5 secs before holding it wide open again. Repeated this till I got to 460. Ease off the throttle and rode lightly to home. The bike dropped to a steady 300s

Is that temp to high?

Yes but I'm no expert. But I always tried to keep my temps under 400 with my Corsa. Can't imagine most kits like those high temps.

Sounds like super lean or an airleak do not ride anymore until you fully check for an air leak. What size jets are you running? You may also want to ride a tad lighter than that. 460 is close to melt down you want 400 to be about max... 300 is a good wot temp. Ask g9, hes the one who knows everything about the bore. Also are you running fan shrouds?