A Detailed Guide: What To Watch Out For When Swapping Power Valve Components Between 200 and 220 Cylinders

[JZ05220r]

Having swapped my 220 kips power valve components to a 200 cylinder, I ended up finding something unexpected that could help someone in the future. The subvalves are inserted in from the top of the cylinder followed by the guides or bushings. The bushings are designed to support each subvalve and keep them from moving up and down from engine vibrations.

I found that the bushings on the 220 are .9mm (17.6mm) taller than the ones on the 200 (16.7mm). So, if you go to use the 220 bushings on a 200 cylinder, they will stick up above the cylinder and the entire power valve system will be locked up after tightening the cylinder head on. You can remedy this by removing material off the 220 bushings but I decided to use the correct part.

On the other hand, if you use the 200 bushings on a 220 there may be excessive up and down movement on each subvalve.

The way to tell the difference is by looking for a groove around the center of the bushings. The 200 bushings have a groove and the 220 don’t. Also, if you look at parts diagrams they are a different part number.

The 200 bushings dimensions are listed next to the part number as 6x15x17.2mm yet that is incorrect based on the 2 sets I got a hold of. The actual measurement is 6x15x16.7mm. No one has shed light on the difference between the bushings as far as I can see.

Lastly, It is known that you never want to mismatch a 200 and 220 main valve to your cylinder. If you have a 220 cylinder use the 220 main valve and vice versa. If not, you will have a clearance issue between the main valve and the piston or you will not be fully closing off the exhaust port at lower rpm’s. Hopefully this helps someone in the future.

[ss109]

Damn good info for those considering swapping to the other. Thanks for posting this up!

[TasKdx200]

Where’s the like button….. thanks for the info.

[billie_morini]

JZ05220r, thank you for sharing this detailed info. It is and will be very useful to many of us.

[JZ05220r]

Another update is needed to complete this topic. The right side covers are also a different part number between the 200 and 220. On the 200 the part number is 14032-1418 and on the 220 the part number is 14032-1419. I found that the governor/advancer shaft sticks up further out on the 200 cover and vice versa on the 220. This leads to a clearance issue when swapping an originally equipped 220 cylinder with a 200 cylinder. The paw gear has some serious binding issues that completely lock up the KIPS once tightened. This can be remedied by shimming below the paw gear. If you were to swap a 220 cylinder to the 200 you will find that the paw gear will not mesh as tightly with the gear teeth on the main shaft. Doesn’t appear to pose a serious risk in performance and function but there are definitely some people who may change their minds on doing a “displacement” swap with this info being available.

[kdxdazz]

Reread this post again, could it be the 220 and 200.have a different deck cylinder height? This would explain the lower compression ratio on the 220 and hence the longer bushings required

[JZ05220r]

Reread this post again, could it be the 220 and 200.have a different deck cylinder height? This would explain the lower compression ratio on the 220 and hence the longer bushings required

I’m not sure but it would make sense if that was the case. Obviously their are many many difference between the two cylinders.

[Chuck78]

Could it be the 220 and 200 have a different deck cylinder height? This would explain the lower compression ratio on the 220 and hence the longer bushings required.

If someone has an uncut 200H cylinder, I can measure my 220 cylinders to compare total deck height. I'd be very curious to know about this...

[kdxdazz]

Could you measure and post please chuck, I have my 220 cylinder off now which I have just had heavily cut because of a bad sleeve install, I'll post the measurements to compare, hopefully I'll get the cylinder on today and check clearances and squish

[kdxdazz]

Here is my cylinder, I'm guessing 0.5mm has been removed, hope it's not more, this is the SR model cylinder

[Chuck78]

Could you measure and post please chuck, I have my 220 cylinder off now which I have just had heavily cut because of a bad sleeve install, I'll post the measurements to compare, hopefully I'll get the cylinder on today and check clearances and squish

Here is my cylinder, I'm guessing 0.5mm has been removed, hope it's not more, this is the SR model cylinder

@kdxdazz, my apologies, I'm quite late in replying... But as I had 4 cylinders on the bench in front of me tonight, I recalled your request to measure the cylinders, which I had put off for the next time I was in the shop, but forgotten about....

The re-plated/ported/70mm +1.00 overbored cylinder I have shows a nice machined head gasket finish which I can only assume, after an acid bath electrofusion plating stripping process in order to re-plate, had been milled slightly.
It measured 105mm tall, head gasket surface to base gasket surface, 0.30mm removed.

The other 3 KDX220 cylinders here all measure 105.30mm tall.

So your 104.77mm cylinder has been resurfaced by 0.53mm.


Now you've got me curious as to the height of the KDX200H cylinders vs the 220 cylinders.


I've finally discovered a good use for A.I., compression ratio calculations based on decked cylinders and cylinder overbore sizes! I always figured despite AI giving endless incorrect information through scavenging forums, that I would find it more useful doing complex math, physics, and chemistry calculations. Now I actually had a practical reason to test that!
My 0.30mm milled cylinder deck surface in conjunction with going from stock 69.00mm bore to 70.00mm bore will bring the low speed compression ratio up from 9.4:1 stock, to 10.03:1... Decking 0.30mm increase it to 9.76:1, the 1mm overbore increases it additionally up to 10.03:1. The 0.50mm x 0.50mm ring of metal I will be removing from the 69mm combustion chamber edge to enlarge it to 70mm will only drop the compression ratio by 0.02 points as it's 69mm i.d. x 70mm o.d. x 0.50mm thick worth of metal renoved... 1.26cc worth of aluminum will have to be removed from the chamber to get to 9.6:1 (slight bump from stock as I only run 90-octane Ethanol-free gasoline), and I will likely be doing this with an SR head to narrow the squish band width slightly, yet it will still be much wider than the stock or RB 220 heads once I'm done, as I do love torque and throttle response...