Author Topic: New pistons  (Read 2770 times)

Offline terryk

  • Valued Contributor
  • ****
  • Join Date: Oct 2006
  • Posts: 460
  • Karma: 3
  • Townsville Queensland Australia
New pistons
« on: 04.03. 2012 13:30 »
Hi has anyone used these pistons from British Only Austria?  They seem very reasonably prices for a pair.
They say they are made in the far east does anyone know where and what quality they are?

http://www.vintage-motorcycle.com/index.php?language=en&site=4&pid=160&id=3524&limit=0
1950-53 A10 rigid/plungers, 1958-61 A10 super rockets, 1947-50 A7 longstrokes, 1949 Star twin,
1951-54 A7 plungers, 1940s M21, WDM20s,
1948-50s B33s rigid/plunger/swingarm, 1948-50s b31s rigid/plunger/swingarm

Offline trevinoz

  • Newcastle, N.S.W. Australia.
  • Wise & Enlightened
  • *
  • Join Date: Jul 2006
  • Posts: 3189
  • Karma: 71
Re: New pistons
« Reply #1 on: 04.03. 2012 19:33 »
Terry,
                 I am running Taiwanese or something pistons in my Flash, similar looking to those from Austria.
They have given no problems to date and are probably much better than some of the old time after market pistons that I have pulled out of engines.

  Trev.

Online Brian

  • Wise & Enlightened
  • *
  • Join Date: May 2007
  • Posts: 1806
  • Karma: 43
  • Mt Gambier, South Australia.
Re: New pistons
« Reply #2 on: 04.03. 2012 21:24 »
Terry I bought a set of those very pistons from BOA. At the time I put some info on the forum about them. Here's a link.

http://www.a7a10.net/forum/index.php/topic,2642.0.html

They seem to be ok, the only problem I had was with the rings. I'm not sure if the rings were dodgy or my pistons had the wrong size rings in the box with them. I used a set of Hepolite rings on them.

I've only done about 2,000 miles on them so far so not really enough to say definitely but they did seem to be well made and everything measured up well etc. Certainly a lot cheaper than anything else.

Offline terryk

  • Valued Contributor
  • ****
  • Join Date: Oct 2006
  • Posts: 460
  • Karma: 3
  • Townsville Queensland Australia
Re: New pistons
« Reply #3 on: 05.03. 2012 09:11 »
Thanks Trev and Brian I now remember reading about your pistons thanks for the feedback.
I will order some from BOA cause they are cheap enough.
I'm building an engine for my nephews 1951 A10 so he can have them in his engine. I'd rather him pushing his bike home then me aren't I a good uncle. Well I am building his motor for free.
1950-53 A10 rigid/plungers, 1958-61 A10 super rockets, 1947-50 A7 longstrokes, 1949 Star twin,
1951-54 A7 plungers, 1940s M21, WDM20s,
1948-50s B33s rigid/plunger/swingarm, 1948-50s b31s rigid/plunger/swingarm

Online KiwiGF

  • Last had an A10 in 1976, in 2011 it was time for my 2nd one. It was the project from HELL (but I learned a lot....)
  • Wise & Enlightened
  • *
  • Join Date: Feb 2011
  • Posts: 1940
  • Karma: 17
Re: New pistons
« Reply #4 on: 05.03. 2012 10:42 »
I had to send my BOA pistons back as the rings and gudgeons were no good.

BOA refunded me postage etc so it did not cost me $$$$ only time!

I bought JP pistons instead from Draganfly, I heard JP rings were no good as well but the rings I got were fine.
New Zealand

1956 A10 Golden Flash  (1st finished project)
1949 B31 rigid “400cc”  (2nd finished project)
1968 B44 Victor Special (3rd finished project)
2001 GL1800 Goldwing, well, the wife likes it
2009 KTM 990 Adventure, cos it’s 100% nuts

Offline Rocket Racer

  • Wise & Enlightened
  • *
  • Join Date: Jun 2009
  • Posts: 1670
  • Karma: 17
  • A kiwi with a racing A10 rig and too many projects
    • NZ Classic Sidecar Racing
Re: New pistons
« Reply #5 on: 07.03. 2012 01:32 »
I wouldnt touch JP's with a barge pole. Tried them several times and had nothing but grief.
I'd be talking to Cake Street Classics who stock wiseco or looking for NOS which is around.
I had far better reliability with taiwanese pistons over JP's.
I'm running good second hand genuine BSA pistons. Lovely and light!  *smile*
A good rider periodically checks all nuts and bolts with a spanner to see that they are tight - Instruction Manual for BSA B series, p46, para 2.
New Zealand

Online KiwiGF

  • Last had an A10 in 1976, in 2011 it was time for my 2nd one. It was the project from HELL (but I learned a lot....)
  • Wise & Enlightened
  • *
  • Join Date: Feb 2011
  • Posts: 1940
  • Karma: 17
Re: New pistons
« Reply #6 on: 07.03. 2012 10:16 »
Yeah rocket racer I heard mixed reports about JP pistons as well from well established brit engine builders in wellington but I wanted std bore flat tops for an A10 and apart from used pistons JP and BOA were the only suppliers i could find. BOA could not replace the duff piston sets they sent me so what could I do......fingers crossed the JPs last OK.

The BOA pistons were really light, lighter than the duff Hepolite equivalents I have.

It's a bit of a joke thats it's cheaper to buy aus made pistons from Draganfly than direct from JP !

New Zealand

1956 A10 Golden Flash  (1st finished project)
1949 B31 rigid “400cc”  (2nd finished project)
1968 B44 Victor Special (3rd finished project)
2001 GL1800 Goldwing, well, the wife likes it
2009 KTM 990 Adventure, cos it’s 100% nuts

Offline terryk

  • Valued Contributor
  • ****
  • Join Date: Oct 2006
  • Posts: 460
  • Karma: 3
  • Townsville Queensland Australia
Re: New pistons
« Reply #7 on: 07.03. 2012 12:30 »
There are a number of A10 owners here in my corner of OZ running JP pistons in street bikes with no problems they seem to like them.
Rocket racer are you racing yours and are they high comp? Maybe the STD flat top ones are ok.
I was a bit concerned with the weight differences between hepolite and and JP so I thought I would go for the BOA ones.
I have a set of STD flat top JP pistons in an A10 plunger I will hopefully have that bike on the road in a few months so I will see how they go. I do have to build another engine for my nephew so I will give the BOA pistons a try as well because they are alot cheaper.
1950-53 A10 rigid/plungers, 1958-61 A10 super rockets, 1947-50 A7 longstrokes, 1949 Star twin,
1951-54 A7 plungers, 1940s M21, WDM20s,
1948-50s B33s rigid/plunger/swingarm, 1948-50s b31s rigid/plunger/swingarm

Online chaterlea25

  • Wise & Enlightened
  • *
  • Join Date: Jun 2009
  • Posts: 4026
  • Karma: 54
Re: New pistons
« Reply #8 on: 07.03. 2012 20:16 »
Hi,
To the best of my knowledge the ""no name"" pistons are the ones supplied by Wassell
I fitted a set to an A10 a couple of years ago , the rings were way out of tolerance but the supplier replaced them with Hepolites, been fine since
Wassel are now selling these ""branded"" as Hepolites as they have bought the name
I'm told the rings are now USA made ?? But I have no experience of these???

I have a new original pair of +0.020 Hepolites 9:1
I would like to trade these for either +030's or 40's,  8.25 or 9:1 or will sell if I get a very good offer and go and buy some Wiseco's

Cheers
John O R
1961 Super Rocket
1963 RGS (ongoing)

Online KiwiGF

  • Last had an A10 in 1976, in 2011 it was time for my 2nd one. It was the project from HELL (but I learned a lot....)
  • Wise & Enlightened
  • *
  • Join Date: Feb 2011
  • Posts: 1940
  • Karma: 17
Re: New pistons
« Reply #9 on: 08.03. 2012 10:16 »
JP pistons have a reputation of being heavy due to being cast not forged but some simple testing I did showed that they were no heavier than some used BSA and Hepolite pistons I have and which are supposed to be forged hence light.

Does anyone know the original piston weights including the oversize pistons and various comp ratios? Did BSA balance cranks to suit different piston weights cos if not then maybe it's not something to be too concerned about as long as the piston is not TOO heavy compared to what was the heaviest OEM piston fitted, which would probably be an oversize high comp piston.
New Zealand

1956 A10 Golden Flash  (1st finished project)
1949 B31 rigid “400cc”  (2nd finished project)
1968 B44 Victor Special (3rd finished project)
2001 GL1800 Goldwing, well, the wife likes it
2009 KTM 990 Adventure, cos it’s 100% nuts

Offline rockthedog

  • A's Good Friend
  • ***
  • Join Date: Oct 2011
  • Posts: 87
  • Karma: 0
Re: New pistons
« Reply #10 on: 08.03. 2012 18:14 »
I had to send my BOA pistons back as the rings and gudgeons were no good.

BOA refunded me postage etc so it did not cost me $$$$ only time!

I bought JP pistons instead from Draganfly, I heard JP rings were no good as well but the rings I got were fine.

i had the same problem exact  *sad2*

Online KiwiGF

  • Last had an A10 in 1976, in 2011 it was time for my 2nd one. It was the project from HELL (but I learned a lot....)
  • Wise & Enlightened
  • *
  • Join Date: Feb 2011
  • Posts: 1940
  • Karma: 17
Re: New pistons
« Reply #11 on: 09.03. 2012 05:19 »
And last time I looked boa don't list online std bore a10 no brand Pistons any more......shame cos you would think it would not be hard to swap the rings and pins for good ones

The other problem is when I asked boa did not know the brand of the pistons and they had no markings either so how can one tell if the pistons were the same brand that have been recommended by forum members etc!
New Zealand

1956 A10 Golden Flash  (1st finished project)
1949 B31 rigid “400cc”  (2nd finished project)
1968 B44 Victor Special (3rd finished project)
2001 GL1800 Goldwing, well, the wife likes it
2009 KTM 990 Adventure, cos it’s 100% nuts

Online Brian

  • Wise & Enlightened
  • *
  • Join Date: May 2007
  • Posts: 1806
  • Karma: 43
  • Mt Gambier, South Australia.
Re: New pistons
« Reply #12 on: 09.03. 2012 05:38 »
The ones I bought were Fuh Juinn brand. They came in red/blue and white boxes with the name clearly printed on the box. I dont think they had anything on the actual piston so if you didnt have the boxes there would be no way of identifying them.

Everybody seems to have a story about pistons and which ones are good or bad, but the next set I buy will be GPM's.