Massive leak from right hand kips cover during leakdown

[JZ05220r]

Here's something I would consider if I had this problem.

First, see if you can find the ID of the bore in new/unworn condition. You may be able to use your old cylinder for this.

Take both of your cylinders to a machine shop and explain your problem. Ask them to measure the IDs of both bores and ask if they can sleeve the oversize bore down to the bore on your old cylinder.

If I'm understanding this problem, this should be an easy fix for any decent machine shop.

Worth a try anyway.

You’re correct that is a possibility. I just wonder if a sleeve would actually be able to fit through the subvalve shaft cap threads to be pressed. Ken O’Connor racing is somewhat local to me and he is a very talented machinist. I will see what he has to say about this. Thanks

[John_S]

I've read a lot of good things about Ken O Conner Racing. Hopefully you guys can come up with something.

[JimmyB]

Any chance you could you post a video of a leak down test, are you loosing pressure from the Center shaft and seal if so this is the cause of the pressure drop, if not its somewhere else. That RH rod part # 46102-1384 and packing part #43049-1076 is a internal part of the motor and I can't see this being the cause of your pressure drop, you could leave that part and packing out and assemble the rest of the motor and do a leak down test to find if the motor is holding pressure, if you are losing pressure that RH Rod is not the cause..

[JZ05220r]

Any chance you could you post a video of a leak down test, are you loosing pressure from the Center shaft and seal if so this is the cause of the pressure drop, if not its somewhere else. That RH rod part # 46102-1384 and packing part #43049-1076 is a internal part of the motor and I can't see this being the cause of your pressure drop, you could leave that part and packing out and assemble the rest of the motor and do a leak down test to find if the motor is holding pressure, if you are losing pressure that RH Rod is not the cause..

The subvalves when closed are not perfectly air tight. Air will easily travel past the right side subvalve and through the packing seal. There are no problems with the left side because there is a slotted cap with an o ring for an air tight seal. By design Kawasaki wasn’t able to get an air tight seal on the right side because of the governor shaft. The main valve shaft is fine as is the seals for it. Thanks

[JimmyB]

Any chance you could you post a video of a leak down test, are you loosing pressure from the Center shaft and seal if so this is the cause of the pressure drop, if not its somewhere else. That RH rod part # 46102-1384 and packing part #43049-1076 is a internal part of the motor and I can't see this being the cause of your pressure drop, you could leave that part and packing out and assemble the rest of the motor and do a leak down test to find if the motor is holding pressure, if you are losing pressure that RH Rod is not the cause..

The subvalves when closed are not perfectly air tight. Air will easily travel past the right side subvalve and through the packing seal. There are no problems with the left side because there is a slotted cap with an o ring for an air tight seal. By design Kawasaki wasn’t able to get an air tight seal on the right side because of the governor shaft. The main valve shaft is fine as is the seals for it. Thanks

Very Sorry, my mistake, WTH was I thinking, for some reason I thought the center shaft seal was on the outer side of the RH rod on the cylinder.
You could try with the packing installed on the RH rod wrapping a few layers of Teflon tape over the packing and install it to see if it makes a difference for the pressure loss, might have to experiment with more layers depending how much it is worn, this won't hold up to running but will give you a better seal for a leak down test or wrap the inner grove for the packing with a narrow piece of Teflon tape to stretch out the o ring, would increase the OD a bit.
You could smooth the rough area, take a 1/4" rod, slot the end of it about 1" lengthwise and wrap it in fine emery cloth and hone it by hand. then experiment with o rings.

[JZ05220r]

Any chance you could you post a video of a leak down test, are you loosing pressure from the Center shaft and seal if so this is the cause of the pressure drop, if not its somewhere else. That RH rod part # 46102-1384 and packing part #43049-1076 is a internal part of the motor and I can't see this being the cause of your pressure drop, you could leave that part and packing out and assemble the rest of the motor and do a leak down test to find if the motor is holding pressure, if you are losing pressure that RH Rod is not the cause..

The subvalves when closed are not perfectly air tight. Air will easily travel past the right side subvalve and through the packing seal. There are no problems with the left side because there is a slotted cap with an o ring for an air tight seal. By design Kawasaki wasn’t able to get an air tight seal on the right side because of the governor shaft. The main valve shaft is fine as is the seals for it. Thanks

Very Sorry, my mistake, WTH was I thinking, for some reason I thought the center shaft seal was on the outer side of the RH rod on the cylinder.
You could try with the packing installed on the RH rod wrapping a few layers of Teflon tape over the packing and install it to see if it makes a difference for the pressure loss, might have to experiment with more layers depending how much it is worn, this won't hold up to running but will give you a better seal for a leak down test or wrap the inner grove for the packing with a narrow piece of Teflon tape to stretch out the o ring, would increase the OD a bit.
You could smooth the rough area, take a 1/4" rod, slot the end of it about 1" lengthwise and wrap it in fine emery cloth and hone it by hand. then experiment with o rings.

No problem man you’re good. It has 2 be the packing that’s the problem. It’s so obvious to me visually inspecting and feeling the difference when inserting the shaft into each cylinder. This 100 percent has to be the issue. I think of people might question why Kawasaki decided to put a seal on the shaft but it is all making complete sense now. I’m going to contact Ken O’Connor and see if he can bore and sleeve it somehow to restore the sealing surface. The left side kips shaft is also corroded but I do not seeing it being an issue. If he can do it for a reasonable price then I am confident I’ll have the cylinder how I need it.

[John_S]

This reminds me...I saw a video a while back from KDXDAZZ where he was trying to seal up the exhaust orings. (Going off of memory here) He took a teflon type of tape and wrapped it inside of the groove and then installed the oring. I wonder if running a layer or two around the groove in your shaft and then installing the packing would give it that little extra size that you need?
EDIT: sorry I see that Jimmy said the same thing above.

[JZ05220r]

This reminds me...I saw a video a while back from KDXDAZZ where he was trying to seal up the exhaust orings. (Going off of memory here) He took a teflon type of tape and wrapped it inside of the groove and then installed the oring. I wonder if running a layer or two around the groove in your shaft and then installing the packing would give it that little extra size that you need?
EDIT: sorry I see that Jimmy said the same thing above.

I believe that was pfte tape. I can try that and see what happens. I wonder if a layer of pfte (high temp tape) would hold up in the long run in the groove below the packing seal.

[JZ05220r]

Talked to Ken today. He said to give it a try and see how it runs. He explained how the Suzuki lt250r engines by design do not hold of pressure with a leakdown tester. He was very interested to see how it goes and asked me to get back to him regardless of the outcome. I’m in good hands with this guy so I’m gonna send it and if anything is wrong Ken said he’ll make it work.

[JZ05220r]

Jeff Fredette sent me an o ring for free to replace the packing seal. It’s a tighter fit so I’m sure it will be a better seal but I still may not have the most desirable leakdown test results. Going to have the bike back together by the end of the week. Finally. A stock ported 220 with the RB mods and vforce reeds, we’ll see how it goes. If its anything like my 91 200 I’ll be happy.

[KDXGarage]

Sweet. Keep us updated.

[Molly's 70]

My Fredette ported 220 w/ RB head & carb mods & Vforce reeds runs really well. I do run VP VPR fuel which is not necessary, but
it sure makes tuning a breeze.

[JZ05220r]

My Fredette ported 220 w/ RB head & carb mods & Vforce reeds runs really well. I do run VP VPR fuel which is not necessary, but
it sure makes tuning a breeze.

I bet it does, I had fun on my 220 when I first bought it all stock besides a silencer, this should be a good middle ground and help cancel out the issues I battled with on my previous cylinder. Would you care to explain how the fuel helps with tuning? Thanks

[Molly's 70]

The VP fuel just brought the bike to life. The air idle adjustments were, I were more responsive. I know it's an oxygenated, leaded fuel.
Other than that, I can say it kicks ass over 10% ethanol 91 octane I can get out of the pump around here. I don't like the way it smells after combustion. It's over priced, but good quality fuel makes a difference.

[JZ05220r]

The VP fuel just brought the bike to life. The air idle adjustments were, I were more responsive. I know it's an oxygenated, leaded fuel.
Other than that, I can say it kicks ass over 10% ethanol 91 octane I can get out of the pump around here. I don't like the way it smells after combustion. It's over priced, but good quality fuel makes a difference.

Good to know it’s pricey but I might try it someday

[KDXGarage]

Call around to see if any shops sell it by the gallon. The first time I tried "race fuel", I got a gallon from a dragster shop.