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ivahandle

Joined:

Feb 10

Posts: 9

ivahandle says:

compression

hi  im trying to find compression psi   for kaw vn1500 clasic n  fi  2002 book says 55to 80 at 300rpm  is that on turnover  people have said u need at least 100 to start mine are 105 back 115 front  starts good but has starting issues early mornings somtimes petrol and spark good any idears thanks

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  • Posted 2 years ago (19 December 2012 11:52)

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smidget

Joined:

Nov 07

Posts: 2411

smidget says:

HI Ivahandle

You could look for the information on an owners website.

Don't know the test result figures you require (I know not helpful) but how are you carrying out the compression test.

Should be done as follows, after all engine parameters are reset to optimum.

Cold test, remove spark plugs, fit compression tester, open throttle wide (this allows air into the cylinder) spin engine over on starter motor until the compression gauge reaches its highest point. Test cylinder 2 in same way.

Refit plugs, take bike for a ride of at least 5 miles.

Remove the spark plugs and repeat as per cold test. now put a known amount of oil into cylinder 1 and repeat, then do the same with the same amount of oil in cylinder 2.

The reason for the compression test with the oil included is to test the piston ring sealing ability, if there is a significatant increas in pressure then the cylinders and rings will need attention.

I would look at the choke side (cold start enrichment system) of things to start with.

More history on the bike will assist in suggested problem cures from those trying to help.

Hope that helps a little.

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AdieR

Joined:

Apr 08

Posts: 3042

AdieR says:

More info needed

what mileage is on it?

Has the bike been stood for any length of time?
 
What are the starting issues (turning over and not firing, not turning at all?).

How old is your battery, and is it fit to survive the current cold weather?

As an aside, when looking for faults, always rule out the simple stuff (battery / electrical / fuel faults) before delving into major stuff (regardless of the "Joe down the pub says" type of advice).

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jaffa90

Joined:

Mar 09

Posts: 8826

jaffa90 says:

starting issues

I think your barking up the wrong tree,As AdieR says more info,also does this problem occur more in cold weather?

These big V twins need a good battery,so what`s the voltage reading before starting? (as in 12.8 volts dc)

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