pretty sure it now isn,t fuel related

fj11.5 · October 22, 2011, 11:16:44 PM

as I couldn't get effie running as she should , no matter what carb settings are FYI 115 main jets, 42.5 pilots needles second slot from the top, seemed to be chocking at 3 , 2.5 turns out, , just checked compression as I had access to a gauge and wasn't feeling too bad today now I'm not so sure , starting. At #1cylinder 100 pSI 75 73 23 shit shit f*##%&ck ,stupid bloody gauge must be wrong, sadly no, , new rings me thinks and someone to install them, , hey Randy ,you busy mate.

Pat Conlon · October 23, 2011, 06:09:08 PM

Was your throttle locked WFO when you did the readings? If not retest.
Because your bike won't start I guess those were cold readings. Squirt some oil in #4 and see if the reading improves, if it does, then it's your rings, if not then check your valve lash. If valve lash is good then you probably burned a valve. A leakdown test will tell you for sure where your compression is going.
I suspect something else is going on with the engine. IMO the low compression numbers is not the reason why your engine won't start. I had very low compression numbers (80's warm) on my old motor and it started just fine.....

fj11.5 · October 23, 2011, 07:42:25 PM

Quote from: Pat Conlon on October 23, 2011, 06:09:08 PM
Was your throttle locked WFO when you did the readings? If not retest.
Because your bike won't start I guess those were cold readings. Squirt some oil in #4 and see if the reading improves, if it does, then it's your rings, if not then check your valve lash. If valve lash is good then you probably burned a valve. A leakdown test will tell you for sure where your compression is going.
I suspect something else is going on with the engine. IMO the low compression numbers is not the reason why your engine won't start. I had very low compression numbers (80's warm) on my old motor and it started just fine.....

hi mate, thanks for the info , no I never opened the throttle, but after the first reading tried the oil , made no difference, so possibly a burnt valve , they were re,shimmed 500klm,s ago reputable mechanic , engine starts fine cold and hot starts , just low on power mid range and up, ,

fj11.5 · October 23, 2011, 07:44:28 PM

Quote from: fj11.5 on October 23, 2011, 07:42:25 PM
Quote from: Pat Conlon on October 23, 2011, 06:09:08 PM
Was your throttle locked WFO when you did the readings? If not retest.
Because your bike won't start I guess those were cold readings. Squirt some oil in #4 and see if the reading improves, if it does, then it's your rings, if not then check your valve lash. If valve lash is good then you probably burned a valve. A leakdown test will tell you for sure where your compression is going.
I suspect something else is going on with the engine. IMO the low compression numbers is not the reason why your engine won't start. I had very low compression numbers (80's warm) on my old motor and it started just fine.....
hi mate, thanks for the info , no I never opened the throttle, but after the first reading tried the oil , made no difference, so possibly a burnt valve , they were re,shimmed 500klm,s ago reputable mechanic , engine starts fine cold and hot starts , just low on power mid range and up, , oh ps , unsure how to do a leakdown test

Pat Conlon · October 23, 2011, 08:14:17 PM

how to do a leak down test

Google "how to do a leakdown test" and it will give you about a bizillion hits

fj11.5 · October 23, 2011, 09:22:53 PM

Thanks, found a leakdown test , have pretty much everything to be able to pump some air in ,

Pat Conlon · October 23, 2011, 09:28:07 PM

Good deal, find out what's going on with #4. Maybe you just need the top end freshened up.... Let us know what you find. Pat

fj11.5 · October 23, 2011, 10:05:01 PM

Thanks pat, ill keep you informed, just wondering ,could a carboned valve cause the problem, as before the s hims were sorted I had been riding to work every day knowing they were way over due and getting harder to start, biut had no choice not too, I'm hoping its not burnt out, but a freshen up wouldnt hurt , maybe early next. Year . Dam it

Pat Conlon · October 24, 2011, 01:55:02 PM

yea, carbon buildup can hold the valve open. Try running a can of Sea Foam thru your carbs and see if that does not loosen up the gunk.
Follow directions. It's gonna smoke like crazy when you do this, no worries. Run a couple of box fans to keep your motor cool.
....but with the neglect on the valve adjustments I'm betting on a burned valve or valve seat on #4. Pat

fj11.5 · October 24, 2011, 08:46:47 PM

Quote from: Pat Conlon on October 24, 2011, 01:55:02 PM
yea, carbon buildup can hold the valve open. Try running a can of Sea Foam thru your carbs and see if that does not loosen up the gunk.
Follow directions. It's gonna smoke like crazy when you do this, no worries. Run a couple of box fans to keep your motor cool.
....but with the neglect on the valve adjustments I'm betting on a burned valve or valve seat on #4. Pat

I'm not betting because I would of lost , did a leakdown on #4 air leaking past exhaust valve,s , didn't bother checking the others , mechanic can do that when I can afford it, would attempt it myself but due to health reasons I may f!@#$@ck it up. At least it wasn't rings, although may as Well replace the lot

Pat Conlon · October 24, 2011, 09:20:12 PM

Pulling the head and sending it in to a shop for a valve job is the easy part. The engine can stay in the bike while you take the head off.
The tricky part is reinstalling the head, getting the pesky cam chain properly lined up with the cams.

Kudos on the leakdown. Now you know exactly what you are dealing with.... Keep the faith.

fj11.5 · October 26, 2011, 04:46:25 AM

priced the exhaust valves today,oem $83.50 each dam expesive yamaha packets again lol,seeing as I was allreading emailing the bike shop a thank you, I asked for a price On new piston rings $187.00 each set, aussie dollers, think the rings Charmaine wait, Android biller save mu for a couple of valves, , Shane a look On rpm,s site but didn't See either ,other than yamaha are there any company,s that sell them,may be cheaper to buy another head? Seeing tan I'm tasmanian, local joke

ribbert · October 26, 2011, 05:35:08 AM

Quote from: fj11.5 on October 26, 2011, 04:46:25 AM
priced the exhaust valves today,oem $83.50 each dam expesive yamaha packets again lol,seeing as I was allreading emailing the bike shop a thank you, I asked for a price On new piston rings $187.00 each set, aussie dollers, think the rings Charmaine wait, Android biller save mu for a couple of valves, , Shane a look On rpm,s site but didn't See either ,other than yamaha are there any company,s that sell them,may be cheaper to buy another head? Seeing tan I'm tasmanian, local joke

"Wiseco" sell OS forged piston and ring sets with gasket kit($200!) for under $800. and can be ordered direct through the agent in Melbourne - Ken Colvin
Noel

ribbert · October 26, 2011, 05:46:00 AM

No luck trying to edit - previous post should have read KEN COLVIN
Noel

fj11.5 · October 26, 2011, 05:55:55 AM

No worries, thanks for the info, , couldn't edit mine either, dam smart arse phones that think they Can spell

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pretty sure it now isn,t fuel related