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Dommie 99 crankshaft

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This is going to sound like an odd request.

I have recently found that the Dominator  99 which I have, has previously been modified to a 500cc in a 600cc crankcase. 

I want to return it to 600cc, so need a crankshaft, barrel, pistons and push rods.

We have  a classic motorcycle club here in South Africa which has lots of old spare parts lying around. But I need to be sure that the parts are correct if I can find them.

However I don't want to strip the 500 until I have all the parts I need.

Can someone help me with information which will enable me to identify these parts if I find what I think are correct, with photos, description, measurements of whatever to help me?

Thank you in anticipation (compliments to Frank 'n Furter).

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Hi Richard, your 500 (88) barrels will have 8 cooling fins top to bottom, 600(99) will have 9.

This makes a quick and easy check when you cant get to measure the bore.

Best of luck.

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After having both an 88 (converted to SS spec) for many years and a 99 for the last 30 years , I would be quite happy with either .  The 88 was far better at high speed,long distance work smoother than the 99 and very reliable with no problem routinely running it up to 7000 revs (where it was a bit too buzzy!) . The 99 has more torque in the mid range but I would not want to run it beyond 5000 revs as not only too buzzy but has a reputation for going bang due to the extra stress on the now too old con rods.If you have some good components in the 88 ,swapping them for some doubtfull new bits or even more doubtfull old bits seems pointless to me.

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The 99s, especially as they get older, are not as robust as an 88. A blow up with an 88 is pretty rare and should it break a rod it is unlikely to break the barrels or crankcase. The 99 if used hard is more likely to break a rod and if it does it will take the barrels with it and if you are even more unlucky cut the crankcases clean in half. I have the evidence...

What you have to bear in mind is that these rods, common to both, are old and of unknown history. How much of their fartigue life have they used up? 10% or 99%? And beung RR56 alloy, they do have fatigue lives. The shorter stroke and geometry of the 88 (for which the rods were designed) seem to give them an easier time in the 88 than the 99.  

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..for your help and advice.

As the bike is not going to be used for much else than occasional runs and shows not requiring  the extra torque and grunt of the 99, I'll probably take your advice and leave it as a 500cc.

Thank you again.

Richard

 


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