Author Topic: Now thats a piston!  (Read 584 times)

Offline dan daughenbaugh

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Now thats a piston!
« on: 20.04. 2015 17:07 »
Hello ALL, Just putting the finishing touches on the old A7 to start this weekends land speed racing season opener. Made some changes to durability and breathability. Enjoy
50' BSA A7 Land speed racer
64' BSA A50C Scramble-ized
67' Triumph Bonnieville (stock)

Online muskrat

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Re: Now thats a piston!
« Reply #1 on: 20.04. 2015 20:50 »
G'day Dan.
What valves are you using? Look to be needing larger than the BVSR. The piston looks to be teflon coated, what breed is it? Offset pin or std?
Best of luck with it mate.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline dan daughenbaugh

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Re: Now thats a piston!
« Reply #2 on: 21.04. 2015 12:59 »
Musky, Intake valves are from the same engine that the pistons are modeled after, Think you used the same type of pistons in your A7, Think 66.6% of another model *shh* I had Ross Pistons make up this set. The black is a hard anodize on the whole piston even under the crown. Top is coated with ceramic. Had to put new valve seats in on the intake side to accommodate the large valve, Just clears the cylinder wall. I also upgraded the through bolts this year to straight 3/8. Welded up the case barrel mouth to accommodate 1/2 steel inserts to take the 3/8 studs
50' BSA A7 Land speed racer
64' BSA A50C Scramble-ized
67' Triumph Bonnieville (stock)

Online bsa-bill

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Re: Now thats a piston!
« Reply #3 on: 21.04. 2015 13:18 »
I notice you like a bit of leverage at times Dan - Now that's a spanner *smile*
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

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Re: Now thats a piston!
« Reply #4 on: 21.04. 2015 21:18 »
Very nice Dan. How did you get over the pin height problem?
 I also did the crankcase mouth mod but only with helicoils.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline dan daughenbaugh

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Re: Now thats a piston!
« Reply #5 on: 21.04. 2015 22:42 »
same way, spacer under the barrel
50' BSA A7 Land speed racer
64' BSA A50C Scramble-ized
67' Triumph Bonnieville (stock)