The knackered crank on the '79 850 has given me pause for thought.
Now, I have a used '79 850 crank in a box and '79 cases and if that's OK, then I'll simply re-do this engine as the original '79 with kickstart and that will be back to square one, good to go. Re-building the kickstart engine's been an idea that's been at me for a while.
However, if the boxed crank is knackered, I still have a couple of 850 engines with good transmissions and a couple sets of 850 barrels/pistons, heads lying around. I occurred to me that if I were to acquire a set of 1000G cases, a 1000 crank and use the 850 barrels+pistons I'd be surely upping the capacity to what? 930cc? 950cc?
Are the wrist pins the same diam 850/1000? Any gotchas with this idea? Will the 850 barrels mate with the 1000 cases?
Previously, I knew there was no upgrade path for the 850 as the 1000 crank wouldn't fit in my cases, but the acquisition of 1000 cases and crank might address that. I'm trying to do without re-boring perfectly sound bores and wasting good pistons that have a hundred thousand miles in them yet.
<edit<
Nah, just realised it's a daft idea - the extra stroke would clatter the pistons off the head unless a base spacer block was used and since this would be a very uncommon conversion, I doubt anybody ever made such a spacer and besides that, it's just an extra place to leak from.
I don't really want to buy a complete GS1000 engine, as the carriage costs to me would be pricey. I suppose I could do it in bits - cases, crank, jugs+pistons, but then I'd be getting away from my idea of re-using as much as possible of what I've already got.
Now, I have a used '79 850 crank in a box and '79 cases and if that's OK, then I'll simply re-do this engine as the original '79 with kickstart and that will be back to square one, good to go. Re-building the kickstart engine's been an idea that's been at me for a while.
However, if the boxed crank is knackered, I still have a couple of 850 engines with good transmissions and a couple sets of 850 barrels/pistons, heads lying around. I occurred to me that if I were to acquire a set of 1000G cases, a 1000 crank and use the 850 barrels+pistons I'd be surely upping the capacity to what? 930cc? 950cc?
Are the wrist pins the same diam 850/1000? Any gotchas with this idea? Will the 850 barrels mate with the 1000 cases?
Previously, I knew there was no upgrade path for the 850 as the 1000 crank wouldn't fit in my cases, but the acquisition of 1000 cases and crank might address that. I'm trying to do without re-boring perfectly sound bores and wasting good pistons that have a hundred thousand miles in them yet.
<edit<
Nah, just realised it's a daft idea - the extra stroke would clatter the pistons off the head unless a base spacer block was used and since this would be a very uncommon conversion, I doubt anybody ever made such a spacer and besides that, it's just an extra place to leak from.
I don't really want to buy a complete GS1000 engine, as the carriage costs to me would be pricey. I suppose I could do it in bits - cases, crank, jugs+pistons, but then I'd be getting away from my idea of re-using as much as possible of what I've already got.
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