Alright, so I've resurrected the dead horse and will proceed to give it just a few more beatings.

I love the wealth of knowledge this site has to offer and I would categorize myself as a pretty savvy user of forums and the search function, but I'm throwing in the towel on this one. I've seriously spent hours going through threads and threads, but I don't think I'm using the right keywords...because i'll get 27 pages of threads.

Help oh mighty search gods!

I figured out one reason why the bike was breaking up in higher rpms. The air hoses connected to the solenoids were cracked...big time...allowing all kinds of air in/out. Fixed, and now I'm off to set the RC Valves, HRC style.

But here's my problem: In order to set them according to HRC specs, the cables are maxed screwed out on one side and screwed all the way on on the other...and I'm still not at 2mm clearance! Not quite flush actually.

Let me make sure everything is what it should be doing:

TPS disconnected, servo goes to "HI".
TPS connected, servo goes 1/3 above "LO".
TPS connected, bike idling, servo goes 1/3 above "LO".
TPS connected, bike running above at/above 2500rpm, servo goes to "LO".

Servo movement is smooth and does what it should, according to all of my reading.

Replaced the cables as I thought the old ones were too stretched (and they were), but I'm baffled. Did the prior owner install the cables incorrectly? The aft cables on the servo go to the aft part on the rc vavle pulley, correct?

Many thanks to any assistance or thread with what I'm trying to look for.

Dana
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2016 Husqvarna 701SM
2021 Husqvarna FS450 supermoto
2014 Honda CRF250R supermoto
1995 NSR250r MC28

Here's a post from Stephen:

"Blip the throttle to over 3k. Mark the postion that the servo goes to at it's highest (hi point)

Stop the engine and turn the servo to your premarked position.

Set the valves up.

The 12k opening of the valves is the same position as the 3k opening.

Valves need to recessed into the roof by around 0.2mm not flush.

Make sure when blipping the throttle the valves open together after adjustment as cable tension makes a big difference to performance."




So when I goose it over 2500 rpms, the servo should move to the "HI" side or to the "LO" side? (Mine moves to the "LO" side) That's one of my major questions. I can't find a post that says what "LO" and "HI" actually means in "open" or "closed" terms.

Dana

If you rev the motor past the "test cycle" the RC Valves will close again. (LO)

Make sure you're not revving the motor too high to find the open position. (HI)
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Andy.
NSR-WORLD.COM

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Just would a normal servo position to be setting the valves HRC style be closer to the HI or LO position?

I tried it again and sorry for my brain just not functioning on this one!

Card in, it goes to 1/2 between HI and LO.
Idling, it stays 1/2 between HI and LO.
2500-ish, it goes to LO. <--this is where I mark it and try to set valves to, right?

Dana

And my brain keeps telling me LO (the RC valves are closed allowing the most exhaust through) is where I should be setting the valves.

Man this sinus infection medicine and gas fumes are making me loopy!

Dana

This is what mine does.

I mark it at the point after I've revved it and it moves to the "LO"? That's where I adjust?

http://www.youtube.com/watch?v=MLfmF4BZHLg&feature=bf_prev&list=ULb0PvKXrVjnU&lf=mfu_in_order

Dana

Why don't you just adjust them normally? i.e. unplug the TPS, turn the ign on then off and line up the marks on the RC valve butterfly and it's bracket.

If that gives a result different to the way you're doing it now, you're doing it wrong.
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Please do not PM me technical questions, if you can't find it on the Forum start a thread

The test cycle for seeing the powervalve servo high position is there so you don't have to rev the bike to 12000 rpm to check the power valve operation or settings.
The test cycle, if I remember right, occurs between around 2500 and 3000 rpm.

You need to be holding the revs constant at the test cycle point in the rev range. This will make the servo turn to the high position.
Low, or LO is when the valves shold be at their lowest position, or closed.

High, or HI is when the valves are open fully, at their highest position.
The HRC method of setting the valves requires the servo to be set to the Hi position.

Remember, to mark the servo you need to hold the revs constant at the point where the servo turns to Hi.

Start the engine and let it warm up. Then from idle, watch the powervalve pulley on the lower cylinder. The little pointer should be pointing forward or to the right. Slowly increase the revs of the engine to the test cycle point and you should see the little pointer move to the left. At this point the servo motor pointer should be pointing to Hi. That is where you mark the servo with a pencil line to get the exact High position.

You guys are awesome! Got it squared away, but I must admit, I have brought great shame to the MC28 owners. So much that I should kick my own ass.

Dana
(still sitting quietly off to the side)
_________________
2016 Husqvarna 701SM
2021 Husqvarna FS450 supermoto
2014 Honda CRF250R supermoto
1995 NSR250r MC28