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Discussion Starter #1 (Edited)
Hi,
I live in Portugal and i'm new here, also new with Ducati!

I bought recently a 750 supersport (V200AA engine), year 2000, with 29 000km (hope so!) and as I'm doing the 3000km revision, I would appreciate the opinion of people that are experienced this 2v engines!


One of the 1st checks was the compression test, the result was:

- HC: 6.5 bar

- VC: 7.9 bar

(Tested with open throttle and after engine running (10 min)).
(The compression rate in the owners manual is 9 +/- 0.5 (owners book))
(The sop manual says:
Standard compression: 9-11 bar
Minimum compression: 8 bar
Maximum allowable compression
difference between cylinders: 2 bar )


After the test (engine cold) I leak checked the cylinder with 2.5 bar and the pistons in the TDC compression. The result was:
- HC: great leak in the intake, medium leak in the exhaust and medium in the engine sump
- VC: no leak in the intake and exhaust, medium leak in the engine sump


No my planning is to polish the valves and seat of the cylinders. Then measure again the compression.


My big question is (supposing I'll put booth at 8 bars):

- Is normal to have about 8 bar of compression at 30 000 km of millage ?
- Would you consider putting a set of piston rings?



.. Hopping my English is understandable! Thank you in advance for you comment!
 

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Rings prob no..
only bars I know serve drinks.. also known as pubs or boozers..

Compression sounds low but sounds like carbon. They are known for valve recessions.

It's too easy to just transplant engines over rebuilding these.. location dependant..

Must admit I think compression testing is a bit like cancer tests... if you don't look then everything is fine..

I've got 76 000 km on my 900 and never tested.
I'll admit to throwing a belt and bending a valve.. stripped it and only did the valve. Put everything back in.

I've always believed that so long as they are close ish it's all good

Good luck.. if you do pull the heads just check bores and lips and forget it.
 

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Discussion Starter #3
Hi Shrek,
thank you for you comment!

what concerns me is actually the diference between cylinders. i also checked the inlet valve and it was closed (not being actuated by the rocker arm).

This weekend i will work on it, the i leave feedback here!
 

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Discussion Starter #4
Here's the feedback:
After disassemble it I found an inlet valve guide craked and the valve was bent (not concentric)...
I decided also to change the piston rings.

Regards
 
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