Kawi2strokes.com Forum

I remember reading here somewhere that with 34mm Mikunis on an H2 the oil pump goes over max rotation and puts to much strain on the oil pump.
Looking at mine it goes past the last mark on the pump by quite a bit.
Is this bad?
Stress on the pump? Or does the pump open to far and stop oiling at full throttle?

I dont expect to be running wide open much, but if one chooses to do it for extended periods would it be a problem?

In a word yes. I solved my problem with this by tapping a 6 MM hole in my clutch cover and using an H1 cable. You will put side stress on the shaft in the pump at wide open with the H2 cable.

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I Love the Smell of Blue Marble in the Morning!!!
Tim Steele in Front Royal, VA
Home of the Phoenix Project
Stay in it when it comes on the pipe, no need to be scared...

As you said, the problem is that the longer travel of the slides makes the oil pump cable also travel farther, kinking the cable a wide-open throttle where it connects to the pump pulley. Tim must have solved it by changing the pump's idle setting, using a different cable. I modified my pump pulley by welding on a new cable bracket to allow the pump to maintain the stock idle setting.

There is a photo in this thread: http://www.kawi2strokes.com/forum/viewtopic.php?f=2&t=9936&p=97380

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If it surges, that's normal, upshift.

Thanks for that link!

Seems like both easy fixes, Thanks.

Jim in your photo if you notice the two "dots" on the pump pulley, for some reason I thought those were index marks and at full throttle the pulley is way past the last index mark.
Since the cable pull is longer the pump is turning further, is that a cause for concern.
Does the pump cam rotate past the point where it is pumping and close shut off after full stock travel is reached?
Or is that not a concern because you are getting plenty of oiling and if it closes off a bit at full throttle the likely hood of damage is minimal unless you were to run wide open for long periods of time?

( I did a search and looked and didn't see the other thread )

As I remember, the extra rotation does nothing to the oil flow. It would have to turn farther than that to start decreasing the oil flow. Maybe Mraxl or one of the guys who have worked extensively with the pump can confirm this.

I can tell you that I've had this setup for about 35 years and I don't have a piston scoring problem.

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If it surges, that's normal, upshift.

I like Jims setup the best.....it makes total sense and cures the issue totally (you could move the tab out so 34mm of travel turns the pump the same as the stock 30mm)

I used an H-1 Bail on my pump, I also back it off just a bit at idle (they are over oiled stock)........the H-1 Bail has a bigger circumfrence, therefore it takes "more cable length" for the same turn of the pump........I still have a little binding, but much better than before.........It also cuts back on the oiling a bit during most street riding

I speak Jim Shreve "Darth" Often (the Oil Line Guy) and we have discussed this about turning past full, have rebuilt a few pumps myself now.......they have to turn quite a bit more before shutting the oil off.........the issue is you DON"T want the tab to break off by overstressing it and killing the system and your motor

You can see in the PIC's (470 H-1 on the left)

THX Phil

I am running a H1 pump on my H2 motor as well.

_________________
I Love the Smell of Blue Marble in the Morning!!!
Tim Steele in Front Royal, VA
Home of the Phoenix Project
Stay in it when it comes on the pipe, no need to be scared...

Those are great ideas, I did it a bit different.

my solution is not for everyone, but is simple. I have the oil pump backed off to the extent that at full throttle with 34s, the pull on the oil pump cable end is still nearly straight. I add about 1.5 oz oil to each gallon of fuel. I believe even with an oil system failure, with today's high quality oil I may catch the problem before having any damage. Like I say, not practical if you are riding cross country/filling up at stations or otherwise riding your bike a lot.

Another possible option, is to put some kind of stop spacer in the carb so the carb slide is what hits first prior to the oil pump cable.

I was looking at it late last night and thought the same thing, the difference in the height of the slides vrs the opening in the carb is very slight and I don't plan on a bunch of full throttle action. The strain on the cable and that tiny metal tab on the pump would still be there at full throttle but it would be straight line instead off to the side.

Im still thinking the best route is Jims by rewelding a new connection.