YPVS question and service manual

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jopi
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Location: Swiss

YPVS question and service manual

#1 Post by jopi » Sun Nov 06, 2016 10:03 am

Hello Guys,

I'm Jonathan, 46 years old.

2 stroke engines were always my passion, and now I finally decide to create a modest collection with Iconic 2 strokes.
I have many aprilia 2 stroke, tzr 125, tdr 125, tdr 250, tzr 250 3xv, rd 350 1wt and

The queen of my collection is clearly my RD 500 lc .

I need you help and have two questions.

1) We work on the engine actually. The engine start good, but power is very low.

I 'm not 100% sure that the YPVS system was correctly mounted on my bike.
Wenn you put the contact, the ypvs system moove. Wenn the check is finished,
where must stop the ypvs lever: in the forward direction or to the rear direction?

Maybe somebody has a picture of this lever with YPVS closed and open ?

2) I'm looking for Owner's manual of rd/rzv 500? where I can found it.

Thanks for your help
Jonathan
2 Strokes POWER :-)

MK
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Re: YPVS question and service manual

#2 Post by MK » Sun Nov 06, 2016 11:25 am

Haven't got it exactly in mind what the wheel between the cylinders does, but the test cycle leaves the exhaust port fully open.
When you start the bike, they close and will be fully open at some 8-8500 rpm.
Unfortunately there are people with two left hands that mistake front and rear valves. In that case all positions are f...ed up.

If you check the connector in the middle of the rear cylinders: Closed means the position "fork" moves closest to the head surface. Open means it's moving away.
The same applies for the front bank, it's just more difficult to check ...

In the "open" position the bore above the exhaust port and the connector should align. Use a long 8 mm bolt to check that.
If you have the pipes off, you should fine tune the position by looking/feeling into the port. The upper edge of the exhaust port must be completely free in open position.

The pic shows the above example with switched valves. In that case the lever and the bore do not line up in open position!
FB_IMG_1478442579311.jpg
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If you don't already have it, you may be interested in my RD500 manual (which I also have for the 350):
http://rd350.gmxhome.de/Muster_TB500_deutsch.pdf" onclick="window.open(this.href);return false;
Bye
Martin

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Speed Freak
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Re: YPVS question and service manual

#3 Post by Speed Freak » Sun Nov 06, 2016 1:44 pm

Also check if the valves move, they often look like this:
Image

I was also missing power on mine, PV`s on the front cylinder were stuck.
My bikes:
RD500 YPVS 1GE
RD350 YPVS 31K 1985
Honda CBR 1000 RR SC57
Yamaha R1 RN04

MK
Posts: 487
Joined: Thu Mar 09, 2006 12:54 pm
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Re: YPVS question and service manual

#4 Post by MK » Sun Nov 06, 2016 3:03 pm

I've seen the valves welded and machined successfully.
So if you have the access to a TIG box and a mill ...
Bye
Martin

jopi
Posts: 3
Joined: Sat Nov 05, 2016 1:37 pm
Location: Swiss

Re: YPVS question and service manual

#5 Post by jopi » Sun Nov 06, 2016 3:31 pm

Hello Guys,

Thanks for your help. I will check tomorrow on my bike. That's strange the engine turn
well but don't have full power!

For the owners manual, every language is ok: English, french, italian, german too.

Jonathan
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2 Strokes POWER :-)

silverstrom
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Re: YPVS question and service manual

#6 Post by silverstrom » Sun Nov 06, 2016 4:27 pm

Digital copies of manuals here http://www.rzrd500.com/500phpBB3/viewforum.php?f=21" onclick="window.open(this.href);return false;

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