Author Topic: Piston clearance  (Read 3446 times)

Online muskrat

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Re: Piston clearance
« Reply #15 on: 09.07. 2018 08:00 »
Just had another look. Whoever did the last hone job should have his hole reamed! Not cross hatched at all, just cylindrical. I'd say the scratches were a big bit of grit, started above the top ring and worked it's way down.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Offline RichardL

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Re: Piston clearance
« Reply #16 on: 09.07. 2018 12:29 »
Ouch! It hurts when you do that! That was a quick hone I did just to see what was there.

Richard L.

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Re: Piston clearance
« Reply #17 on: 09.07. 2018 20:34 »
OK your forgiven.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Offline coater87

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Re: Piston clearance
« Reply #18 on: 10.07. 2018 18:49 »
 I would run it, knowing that next time it is getting bored or sleeved.

 If its really bad, you can rev the bike a bit than crab backward into the cloud. Mosquitoes dont like that. ;)

 Lee
Central Wisconsin in the U.S.

Offline RichardL

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Re: Piston clearance
« Reply #19 on: 11.07. 2018 03:39 »
I wonder if the rings will form to the scratches and slowly improve the seal.

Richard L.

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Re: Piston clearance
« Reply #20 on: 11.07. 2018 08:43 »
 *bash* *pull hair out*
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Offline BSA_54A10

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Re: Piston clearance
« Reply #21 on: 11.07. 2018 09:40 »
Having ridden about 15,000 on a barrel that has a gudgeon groove down the side about 5mm deep, go ride it.
It will loose a bit of compression on the bad side and when running wide open throttle the breather will become an oiler.
Apart from that enjoy your bike and save up for a set of oversize pistons.

These are BSA's and they will bloody well run with  a lot more damage than that.
If a bit of smoke & oil worries you then buy a Honda.
Back in the 60's we ran on a lot worse that that.
Had a riding mate who rode to uni for 3 years on one cylinder cause he was broke and could not afford a new set of barrels so he took the adjusters out  and put a PCV valve in the plug hole.
It was a touch on the jerky side in heavy traffic and would have made embarrassing noises if the mufflers had any baffels in them, but apart from that it got him to UNI 4 days a week, out with us on the weekend, down to the pub Friday & Saturday nights , to footy on Sunday then back to Coledale Leagues club Sun evening then back to uni next week. And a lot of this was 2 up
Mind you we were a touch on the lighter side in those days.

It seems to me that the bulk of BSA owners seem fixated on reasons not to ride their bikes rather than getting out there & enjoying them.
Bike Beesa
Trevor

Offline RichardL

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Re: Piston clearance
« Reply #22 on: 11.07. 2018 12:28 »

If a bit of smoke & oil worries you then buy a Honda.

It seems to me that the bulk of BSA owners seem fixated on reasons not to ride their bikes rather than getting out there & enjoying them.

Trevor,

Thanks for this advice. The collective opinion (including mine) is clearly to just run it. I'm glad to see you in this group.

As for oil and smoke, the A10 has its share and I value the exhaust and pavement markings as proof of my dedication.

As for riding, I try get out frequently. Maybe it's a failure of my imagination, but the geography outside Chicago gets a bit boring unless you set out on rides that are major commitments rather than casual outings.

Richard L.

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Re: Piston clearance
« Reply #23 on: 11.07. 2018 13:51 »
The worst ride imaginable is better than the best day at work. Even riding around the block 20 times is still a ride.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Offline BSA_54A10

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Re: Piston clearance
« Reply #24 on: 12.07. 2018 14:42 »
The worst ride imaginable is better than the best day at work. Even riding around the block 20 times is still a ride.
Cheers
[/quote

OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?
OOH that's a nice garage I wonder if there are any motorcycles in there ?

Perhaps I should have gone to work today I am getting dizzy

OOH that's a nice garage I wonder if there are any motorcycles in there ?
Bike Beesa
Trevor