30 minute sessions and letting a Moto America rider thrash i

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pstamper
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30 minute sessions and letting a Moto America rider thrash i

#1 Post by pstamper » Sat Aug 20, 2016 2:38 pm

Blew head gasket but Rick came through and new one here Monday. An Evening to put back together and sync carbs. Hope all goes well with track weekend at COTA next weekend. Will be in upper 80s. tJImage

Luther
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Re: 30 minute sessions and letting a Moto America rider thra

#2 Post by Luther » Sat Aug 20, 2016 7:15 pm

Hi Paul? I haven't been here in a few years and its really cool to see your posts and pictures of a 30 year old 500, conservatively modified, getting pushed to the limits at a couple of really fast tracks. It can be done. And RZ500's set up well are a fun bike to go fast on.

I wanted to take advantage of your pic here to point out a couple things to the crowd. Before you put the headgasket on lay a 12" or 300mm straight edge across the tops of the cylinders several ways to see that its flat one cylinder to the other. Then check the head is flat. Many years ago I measured the length of my cylinders and found one was .008" or .2mm shorter than the others. It was holding pressure fine but I cut the 3 long ones. For years I've been getting away with 2 layers of stock gasket, rubber scrubbed off and spray on copper coat. When you have cylinders off check the case top to know its flat. A really anal mechanic will put cylinders on with nuts finger tight, then put head on no gasket and tighten the nuts snug, then tighten the cylinder base nuts, take head off and check for flat, finish with gasket and head.

On each side of the head stud over the exhaust port is the coolant passage that loops around the exhaust port. Bend a piece of wire to probe down each side about 30mm to feel how much casting flash might be blocking the passage. If its bad you can heat a 4mm coarse round file kind of S shaped to clear it out.

Hey Tom, thanks for the forum, I never would of got my bike running without it.

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Re: 30 minute sessions and letting a Moto America rider thra

#3 Post by pstamper » Sat Aug 20, 2016 10:42 pm

Thanks for compliment and i really do enjoy taking the bike out. Every year I get more comfortable with it but also a year older. I checked the head and cylinder with a long stainless ruler. All is good. We are thinking that the heat and the longer sessions on the private track day let a head nut get loose. When I loosened them one seemed easier to remove. I will install new gasket torque to 16 Ft/lb, start it, let it get hot, and recheck torque. I usually have a centrifugal blower that I set up at track so when I pull in the engine gets some extra cooling. I have been paying more attention to tire pressure so I found out what happens when you get complacent. The fan is coming back out next weekend if all goes together well.

The bike does very well and I would like to see one of the inline 4 cylinders have a head removed in 45 minutes.

thekelzer
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Re: 30 minute sessions and letting a Moto America rider thra

#4 Post by thekelzer » Sun Sep 25, 2016 1:06 am

pstamper wrote: The bike does very well and I would like to see one of the inline 4 cylinders have a head removed in 45 minutes.
No doubt right !

I love watching your videos so much, I pulled my bike from the dealership display it has been sitting at ! I sure wish I had access to a track over here.....#islandlife

Aloha,
Kelly

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Re: 30 minute sessions and letting a Moto America rider thra

#5 Post by vma500 » Mon Sep 26, 2016 7:16 am

nice tips from Luther :grin:

also retorque the center nuts when u torqued all the headnrs

i use always loctite 3020 spray on all gaskets
my bikes :RD500 2X ,RD 350 F2 , RD 350 31K,RD350 4LO,RG500,RG250 WW,RGV250,TZR250 3MA,TZR250 3XV,NS400r,NSr250 mc21,KR1250S,

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