Page 1 of 1

Idle and break-in

Posted: Tue Mar 27, 2018 5:20 pm
by Felix
Finally got my engine done. New bore, valves and Robbins piston with barrel shim. The new carb (PWK) adjustments actually work since the inlet valve now seals properly. Runs much better overall and I added a cheap tach to keep an eye on revs. What should normal idle speed be and what should break-in RPMs be limited to?
2000 Iron 500.
Image

Idle and break-in

Posted: Tue Mar 27, 2018 7:27 pm
by Leon Novello
Something to read whilst waiting for other replies. As for idle speed, I would set it so it starts and idles from cold without stalling, but not so fast that you can`t get it into gear without grinding the teeth.
http://mototuneusa.com/break_in_secrets.htm

Idle and break-in

Posted: Tue Mar 27, 2018 8:44 pm
by PeteF
It's not the revs that matter so much (within reason) but the load on the engine. Keep it spinning but don't twist that throttle too much.

Idle and break-in

Posted: Wed Mar 28, 2018 7:53 am
by Presto
This may be some help: After fitting a new piston for the first 50 miles the engine should be used VERY carefully; for the next 150 miles use very light throttle openings; during the first 500 miles avoid any sustained ‘high’ speed use – i.e. above about 50 mph for any length of time; the engine must not be allowed to ‘labour’, or run for an excessive time with the bike stationary; avoid any use that causes the engine to generate more than ‘normal’ heat; gradually build speed, with short bursts of speed, until the engine runs at full potential by about 800 miles.

Idle and break-in

Posted: Wed Mar 28, 2018 2:59 pm
by stinkwheel
Last piston change on the 350 I did the technique Leon posted. I effectively did "hill reps" to get it loaded properly. Oil and filter change after 200 miles.



Nobody died.

Idle and break-in

Posted: Wed Mar 28, 2018 4:40 pm
by Felix
Thanks, folks.
I'll use Presto's advice and go by feel and the speedometer. After waiting for mail orders and machine shop work, I want to treat it right. The shop took a month to cut seats and replace guides!

Idle and break-in

Posted: Wed Mar 28, 2018 9:13 pm
by Alan R
WHAT !!!---A MONTH ??-That's ludicrous !!----Felix, that head job should be turned around within a working day !!..two at the most.( I'm assuming that you supplied a fully stripped head and they didn't encounter any problems or had to wait for spares ??).....Give me their address and I'll send "The Boys" round for a chat !!------------- Image

Idle and break-in

Posted: Thu Mar 29, 2018 4:00 pm
by Felix
Alan,
There's no riding season here, so the moto machine shops are always packed with work. A bore, guides and seat cutting came to $320.
The only other bike machinist is pricier and drones on about Mr. T.



Idle and break-in

Posted: Thu Mar 29, 2018 4:09 pm
by Alan R
Hi Felix-----------just a thought but you could have air freighted it to here----had it done and returned within a two-weeks..OK, I'm being a bit silly but a MONTH !!--ye gods..Anyway, all's well now so bed-it in using your method of choice and let's see the results very soon, please ??