Compression test data required

[OogieBoogie]

Hi all,

Does anyone have the definative answer to what a 'good' compression test reading should be for the Morini Kanguro. I know it can be worked out from the bore, stroke and compression ratio but I don't know how.

I'm getting quite a lot of fumes from the engine breather which makes me wonder if my rings are worn or gummed up, after all the bike was laid up for over 3 years.

It also seems a bit harder to start than I remembered (perhaps I've just lost the knack) and may be lacking power (or perhaps I'm just spoilt by 3 years of Ducati ST2 grunt), the light weight, light handling and sit up riding position is great after the Duc though (for commuting).

Stu.

[robinh44]

Stu,

When I had worn rings on my kanguro the symptoms were easy to kick over and poor idling. I checked with my compression gauge and it was outside of the green healthy zone which was around the 100-120 psi mark. I stripped down the head and barrels and measured the ring end gaps and both bores were outside of spec. I would suggest a strip down checking valve clearances as a start, then check heads and valve seats before moving onto rings. How easy in terms of effort is it to kick start, do you feel any resistance at the compression point?

Regards

Robin

[OogieBoogie]

Hi Robin,

I need to check the valve clearances for sure, but I'm not too keen on stripping the top end down unless I'm absolutely certain the rings are worn. On the way home tonight it seened to be pulling really well. On the stretch of dual carriageway buzzing allong between 130-150kph so in reality probably 75-85mph. Still noticing that oil fumes smell from the breather when I park up though.

At the weekend I think I'll get new plugs, do the tappets and check the compression (If I can get my dad's old compression gauge in to the rear plug hole).

I'm quite enjoying the winter commuting despite the frost the last couple of days, I don't mind the cold (for limited periods) its the rain that gets me reaching for the car keys.

How's the special, been out on it lately?

Stu.

[robinh44]

Stu

Yes performance-wise it sounds ok, the biggest clue on mine when the rings were worn was that when I start mine I push the kickstart until I feel the compression stop it, but I was able to push past the compression with very little effort. Regarding breather I run the three breathers from crankcase and both heads into a water bottle under the seat, as before that I got a lot of moisture running out over the exhaust ( possibly made worse due to short journeys).
I have been out on the special trying out the different screen after I swapped screens with my latest addition a 1993 Yamaha XV750, the special is still running well. Have mistimed the weather forecasts recently and got caught in the showers on sunday. Hope you get yours sorted, keep us informed.

Robin

[John Bunting]

HI Stu & Robin,
I checked my 500 Strada about a year ago and it was reading142 and 144psi, If that is any help to you.
Regards
John