The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: tiggy on 08.11. 2016 18:15

Title: Running in procedure - any advice please
Post by: tiggy on 08.11. 2016 18:15
Can anyone offer advice on best practise to run in a fully rebuilt engine please? Bottom end done, rebore, plus new valves and guides.
Type of oil, frequency of change, revs. etc.
Expensive job to mess up!
Any help gratefully received.
Thanks
Title: Re: Running in procedure - any advice please
Post by: metalflake11 on 08.11. 2016 18:35
Small throttle openings, let it rev out, and as little load as possible. Change oil after first 50 miles, again at 500 and 1,000 intervals after that. I would use straight oil personally, 30w in this weather. (UK)

Good luck, happy running in!
Title: Re: Running in procedure - any advice please
Post by: Greybeard on 08.11. 2016 19:30
Small throttle openings, let it rev out, and as little load as possible. Change oil after first 50 miles, again at 500 and 1,000 intervals after that. I would use straight oil personally, 30w in this weather. (UK)

Good luck, happy running in!

I agree but others here may advise a more aggressive approach. I use 40w single grade oil.
Title: Re: Running in procedure - any advice please
Post by: mikeb on 09.11. 2016 00:32
i recently did what metalflake said. worked out so far i think.

the trade off is between rings wanting some edge to bed in so the bores don't glaze, while the bottom end wants a gentle time as the shells bed in. Also make sure that early miles are not steady speed/ steady revs miles (like motorways) and don't go over 1/2 max revs / 45-50 mph in top for the first 500mi. so find some gentle hills and have some well earned fun. when you get to 500miles-ish give it some wrist but again without low rev / high loads.

others views on this forum are to cane it (high varying revs) asap to help the rings seat - stay above 3000rpm with low load.  *eek*

given that some of the very knowledgeable people on this forum have differing views I figured there was no one right answer. And as a bore is easier to hone that a bottom end to re-shell, I went for the more gentle option.

do replace the oil a lot as metalflake says. and enjoy the fruits of your rebuild
Title: Re: Running in procedure - any advice please
Post by: BSA_54A10 on 09.11. 2016 05:08
Mike has it, a trade off.
I bed in the rings first and once thy have sealed , about 1/2 mile usually I then nurse the engine if I have done bearings & bushes.
This works if the rings have gone in dry.
If you drowned them in oil when fitting then it is a long an winding road ridden conservatively .
In either case, what is vital you do not leave the engine idle , no load.
If it starts, jump on & ride it.
Then when you get back fiddle with the carb, and then out on the road again.
The fastest way to glaze a bore is to have the bike sitting in your drive for 1/2 hour idleing while you try to tune the carb, chasing the changing amount of piston seal up & down the throttle stop.
Title: Re: Running in procedure - any advice please
Post by: BSARGS650 on 09.11. 2016 09:52
Quality rebuild paying attention to tolerances.  Quality oil.  Easy for 10 or so miles to make sure nothing has dropped off and no odd noises, then gun it, don't let it labour......
Title: Re: Running in procedure - any advice please
Post by: BSARGS650 on 09.11. 2016 09:54
Oh, and change oil after 50 to 100 miles with again quality stuff.......
Title: Re: Running in procedure - any advice please
Post by: Rocket Racer on 10.11. 2016 03:59
You can always follow the manual
Title: Re: Running in procedure - any advice please
Post by: mikeb on 10.11. 2016 04:05
RTFM??  *evil* *angry* >:D
where's the fun in that
Title: Re: Running in procedure - any advice please
Post by: Triton Thrasher on 10.11. 2016 06:42
I think the big end shells are pretty well irrelevant to the procedure.
Title: Re: Running in procedure - any advice please
Post by: Klaus on 10.11. 2016 09:02
I run in my engines stationary. All you need is a fan and well understaning nightbours.
Instal the fan close to the engine and run with approx 3000 revs ( the engine) for ten minutes.
Let the motor cooling down and check valve cleanace. This is very importand by new rebuild heads, because the valves placed.
Drain oil and make a change. You need only 1 liter for a change.  Do this tree times and you engine is ready to cross the world provided that the ignition is correct and the carbsetting the best way for your engine.

The only things that had to run in, are the pistonrings also  cam and followers.
Conrods have friction bearings, there is nothing having contakt, if when the oilpressure is collapsed.

I do this procedure to my race enginges and have best experiece with. There is no time at the track to run in, pre start and than full throttle. Whats got for racing that surely not the wrong way for touring.

cheers Klaus
Title: Re: Running in procedure - any advice please
Post by: tiggy on 11.11. 2016 16:22
Thanks for all the help and great advice. Fantastic responses for what I thought everyone would think was a boring post.
Thanks all
Rob