cost estimate - rebuild engine and gearbox - ???

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i know this is subjective, with lots of gray areas. I may be looking at another project bike soon. I have a good idea on what things cost to recondition, restore, refurbish, etc., but having never rebuilt an old british 2 cylinder, I have no idea on costs. so my question, what would be a good estimated price to rebuild a typical 2-cylinder engine - assuming you did most of the labor yourself, but had most of the machine shop work farmed out? this would include a top end rebuild. need something in the ballpark - some dollar amount for price negotiating purposes - $500, $1000, $1500, ???, assume the engine is not frozen, but needs rings, bearing, etc.. a typical rebuild. same question on an average gearbox overhaul. TIA....
 
What it cost me with my labor for a pre OIF Triumph 650 was about $700, my Norton 850 I just finished was about $1300. That was bore plus .020" on both and new pistons. I did everything else. What "British twin cylinder" is it ???
 
What it cost me with my labor for a pre OIF Triumph 650 was about $700, my Norton 850 I just finished was about $1300. That was bore plus .020" on both and new pistons. I did everything else. What "British twin cylinder" is it ???
thanks for the reply. the brit twin is a 650 BSA. my semi-educated guess for an engine overhaul was $1K - i was figuring $500 on a gearbox. right now, from what i understand is the bike's been sitting for several years. the engine turns over, and it ran when parked (dry storage). i have to figure worst case scenario. probably should have posted this over on the BSA site, but for just a ballpark, rough estimate, a twin's a twin. just want some "hands-on" numbers from folks.
 
Exclusive of parts and my own labor, I paid about $225 to cut valve seats and surface the heads and $150 for vapor honing of engine and gearbox cases. Parts on the other hand stacked up, from gaskets to bearings to pistons to nuts and bolts. And don’t forget specialty tools. They are a must. It is such a rewarding experience though.
 
if you are doing head work, i'd suggest talking to Jim Comstock for rates, but you can easily go through $1000. to refurbish the head for the 3 stub repair, exhaust ports, and misc CNW fasteners
 
It really does depend on what one means by ‘rebuild’...

To strip and inspect the engine and re assemble having replaced only what was out of tolerance is one thing.

To strip an engine and rebuild it to a ‘better than new’ standard replacing everything that’s less than perfect, and then a few of the modern available ‘upgrade‘ choices , is quite another thing entirely.

Plus everything in between the above two.
 
I said that to myself some years ago when I embarked on a Vincent engine rebuild.
I was wrong.
Very. Bloody. Wrong.
i totally understand that - just need a ballpark number. i can do fair amount of minor shop work , and do have access to a machine shop. there's so much gray area within this subject that coming up with an exact number would be near impossible.
 
It really does depend on what one means by ‘rebuild’...

To strip and inspect the engine and re assemble having replaced only what was out of tolerance is one thing.

To strip an engine and rebuild it to a ‘better than new’ standard replacing everything that’s less than perfect, and then a few of the modern available ‘upgrade‘ choices , is quite another thing entirely.

Plus everything in between the above two.
agree, lots of gray area here. probably looking for a "strip and inspect the engine and re-assemble having replaced only what was out of tolerance" number" and doing most of the work myself.
 
It all depends on how much there is to do. Done on a 650SS.
AMC gearbox. 2 pair of gears. All bushes. 1 ball bearing. Kick start pawl + pin. Gaskets + seals. Some small parts. £406.69
Engine. Reground crank. Conrods. Valve overhaul kit. Pushrods. Bearings. Gaskets +seals. Oil pump. Some other parts. £1163.20.
 
The A65 costs depend on the timing side bush, lowest cost would be a new bush plus line reaming, highest would be the needle/ball combined replacement.
 
$1,000 - $1,250 unless something like a crank journal is trashed.

On a BSA I'd do a bearing conversion on the timing side, and an oil pump upgrade, so that adds another $500+
 
$1,000 - $1,250 unless something like a crank journal is trashed.

On a BSA I'd do a bearing conversion on the timing side, and an oil pump upgrade, so that adds another $500+

Hey Joe, I agree with GPZ on the BSA timing side needle bearing conversion. I WOULD NOT rebuild a BSA twin without that modification. IMO, the stock timing side bush is a poor design to put it lightly, and to put it harshly, just rubbish. Just my two cents ...
 
realize the wrong forum, but this MAY be my next project - 66 spitfire Mk2 (comes with the original GP carbs). #'s match, ran when parked, repainted wrong color. just got to get the thing for the right price...

cost estimate - rebuild engine and gearbox - ???
 
Nice looks all there, just remember they have a timing side bush that controls the oil pressure.
 
Hey Joe, I agree with GPZ on the BSA timing side needle bearing conversion. I WOULD NOT rebuild a BSA twin without that modification. IMO, the stock timing side bush is a poor design to put it lightly, and to put it harshly, just rubbish. Just my two cents ...

I'm sending my 70 A65 bottom end to Frank Diehl in NC for the bearing conversion
 
Ran

when

parked.......

:rolleyes:

Translated, it MAY have been mostly worn out, improperly stored, repaired by shadetrees (or worse) etc.
Could be a gem.
Up to YOU to to do as much triage as you can, to determine condition, AND leave $$$ for the unknown.
Bright light, little tool box, something to lay on, note pad and a full hour to inspect.
Look at every exposed fastener, to get an idea how "screwed with" it could be...
Ask to see ANY available documentation, however slight.
 
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