RG150 Powervalve adjustment probs

[Jase W]

Hello all, I have been having problems with powervalves on my rg150 since I got it running and started racing it this year. Usually I end up adjusting them so they are open or almost open all of the time, which is fine but I'd imagine not too good for the actuator, and I'm not sure if that is still giving me full power.

I have just adjusted them as per the manual, however the cable slack part has got me a bit stuffed (ie how the hell do you adjust the slack?). Anyway I took it for a ride and its revving up nicely all the way through but stopping dead at just a touch before redline (13000), where it starts coughing and spluttering. To me this feels like it is running out of puff before it should, however I have tried a couple different adjustments - before doing it by the book I just felt up into the port to check the valves were flush with the port (I had assumed that when you touch the wire to the battery, that is the maximum opening for the actuator which I have found out today is actually its halfway point). That method did not work, which means so far doing it by the book has worked best (funny that!).

A thought struck me while I was riding today - I had forgot that I have changed the sprocket sizes. It is running 15f 47r (I cant remember what stock is). Is this likely to be why I think I am running out of puff?

Any thoughts? Should I keep trying to adjust them or is that as far as I am going to get and I am worrying about nothing?

[RDjase]

get hold of ryanf062 , he races one and should know what to do, the power valve is there to create bottom end power by staying closed and having tame port timnig at lower Revs , and opening up when the rpms increase,

having them open all the time will make your engine very peaky. Im just susing my RGV250 with power valve issues at the moment too mate

Try www.rgv250.co.uk it for 250s but may help with info or have a link for 150s. Im new to Suzukis all my bikes a yamahas

[Jase W]

Cheers for that, yes I understand how/why they work I just need to make sure they are opening fully haha! Otherwise they will be creating a restriction in the exhaust port which will limit its power at the top end, which is what I suspect (paranoid perhaps?) is happening.

[Jase W]

Have had a good look on RGV250.co.uk (I have an RGV as well heh), but unfortunately the RG's powervalve actuation system is very different from the RGV, and no one really knows much about the RG as it is only available here and in Thailand. Thanks for your input though!

[RDjase]

Have had a good look on RGV250.co.uk (I have an RGV as well heh), but unfortunately the RG's powervalve actuation system is very different from the RGV, and no one really knows much about the RG as it is only available here and in Thailand. Thanks for your input though!

what model RGV have you got , ive got a VJ21, good for post classic and F3 , when it goes again lol

[MDR2]

Erm isn't that about where the limiter is on a little RG? Also, you're probably not gaining much at all by taking it to the red.

[Jase W]

I have no idea where the limit is usually, hence why I'm putting the question to you guys heh. You could very well be right - I am chasing extra power in the top that just isn't there.

RDjase - mines a VJ22 so good for F3 but no good for PC :(

[MDR2]

Peak rpm's th obe shifting at are abut 10'500 if i recall correctly, anything else is just abuse.

(your rg may have been touched by god and be completely diffeint to mine however) :)

[eelracing]

If you can then take it out for a scoot and get her nice and warm.
Wind her out in a high gear (Same as for a plug chop)ie holding throttle open at or around the redline and pull in clutch at same time as hitting the kill switch.Your valve should now be at the fully open stage.

Don't turn the kill switch back on but do turn the ignition key off (if ya race bike still has it).

Now get the exhaust off and have a good look up in the exhaust port and see/feel where the powervalve is at.

Had same coughing/spluttering probs at the top end with my RGV250 which was cured by a brand new battery.But i run a total loss system and not sure of the rules for your RG.But hope it helps.

[ajturbo]

i have seen 16k on the rev counter...

they WILL handle 13-14k during racing conditions....

if you have followed the procedure to ajust them, all should be fine...
check your gass.. or PM OYSTER he will know or BILLY..

[koba]

Cheers for that, yes I understand how/why they work I just need to make sure they are opening fully haha! Otherwise they will be creating a restriction in the exhaust port which will limit its power at the top end, which is what I suspect (paranoid perhaps?) is happening.

Adjust them by the book, if is coughing and spluttering high up it isn't that the powervalves aren't open fully, that will just flatten off the top of the power.

Put a new plug in and make sure your battery is perfect. also check the main fuse holder is in good condition and holding the fuse properly.
Check the plug cap and HT lead and the LT wire to the coil.

[quallman1234]

Are you sure its not just hitting the limiter? There is a limiter on them at about 13ish or just before and it feels like you hit a wall.

[ajturbo]

Are you sure its not just hitting the limiter? There is a limiter on them at about 13ish or just before and it feels like you hit a wall.
err... not on the bikes i used to have matey,,,...???

[FruitLooPs]

PM Oyster I believe you can adjust the powervalves to work a smidgen better than aligning them strictly by the book.

I know he has a cool wee tool for just actuating the valve motor which makes sorting them out pretty straight forward. :niceone:

[oyster]

In racing best acceleration is given revving from 10500 to 12500. After that there's less power so going there will only make you slower. Also, piston life reduces dramatically in that last (extra) 1000rpm.
Take the little cover off the front of the barrell and when the lead is earthed out the stems should be about 2mm below flush. Zero backlash in the adjusting cables. That's it. The way the book says is a lottery.
In racing they never close anyway. I've ridden one with the valves permanently open and there's no difference at at all, unless you're really duffing it up and trying to drive out of corners at 7000rpm.
My homemade powevalves are the same, tho the step at 8200 is more noticeable than the std ones. There are quite a few out there now in both race and road use, all customers very happy!

15 / 47 gearing is way too low. Down here they're all 17 / 47or48
A good Rg will pull that at all our circuits, with a bit of over rev for drafting /tailwind, common at Teretonga. But at Manfeild I guess with the little straights 16 / 47 OK

[ajturbo]

luke and i found the 16 on the front worked well at manfeild....

[Jase W]

Brilliant! cheers for the help. Gearing was suggested to me by a friend, but I will have a play with it...

[7mmWSM]

Manfeild Short = 17-48
Manfeild Long = 16-47

[quallman1234]

Trust me theres a limiter on my one, its like hitting a brick wall if you don't change before it i think koba has one too its at about 13 and a half tho

[ajturbo]

i wish luke's old one had one... lol

[Jase W]

yeah hitting a brick wall sounds about right!