ESE's works engine tuner

[2T Institute]

Hooked

Well I just spent the afternoon riding a couple of RGVs around at Manfield. So totally hooked on the things now. The handling was a bit poo, but when on the pipe I just wanted the fun to never end.

How many ponies do you {you being the people that know ie not me} could squeeze form an RGV250? I think one had a good 65 maybe and the other maybe low 50"s

So much fun. I see why you are all so mental now.

You can get 65hp with just bolt on bits and an ignition. However, you will run into the problem of the shit RGV piston which at 65hp is at their limit. The pin boss will disintergrate and take out the cylinder on the right that or the tang between the arch will break off.
A YZ125 piston is better to use, cranks are easily rebuildable and you use a DT or LC 125 rod for big improvement over standard. We change them to bottom guided thrusts good to 12,500 now.
Free hp available in keeping coolant temp under control which run over 70deg.
Been using Nitron rear shocks which tick all the boxes.

[FastFred]

http://www.nzsuperbike.com/2013/07/a...aign=bp_recent



Av takes 3rd in Italy,



Av with her Mum and The Team.

[TZ350]

You can get 65hp with just bolt on bits and an ignition. However, you will run into the problem of the shit RGV piston which at 65hp is at their limit. The pin boss will disintegrate and take out the cylinder on the right that or the tang between the arch will break off.

A YZ125 piston is better to use, cranks are easily rebuild able and you use a DT or LC 125 rod for big improvement over standard. We change them to bottom guided thrusts good to 12,500 now.Free hp available in keeping coolant temp under control which run over 70deg.
Been using Nitron rear shocks which tick all the boxes.

Hi Rich

We have been using original RGV rods centered in the piston boss and regularly rev them to 13k plus. I recall hearing somewhere that if the rod has to much side play it can vibrate and eventually break.

2T thanks, its interesting to hear that the 5mm longer LC rods are OK to use.

We also use early 56mm Wiseco YZ pistons.



The YZ Piston Crown Height as measured from the centre of the pin to the top edge of the piston is 0.4mm shorter on the Flat Top 1993 YZ piston (629M) than the RGV and the Domed 86-88 YZ piston (559M) is 0.6 (aprox) taller than the RGV.

[dinamik2t]

Have you ever tried the super-short Cagiva Mito pistons, TZ ?

http://www.mitaka.co.uk/CATALOGUE/VERTEX.htm

[2T Institute]

Have you ever tried the super-short Cagiva Mito pistons, TZ ?

http://www.mitaka.co.uk/CATALOGUE/VERTEX.htm

Yes they are a great piston miles better than th RGV shitters.

Rob I don't use RZ or LC 250/350 rods but I found a 125 either DT/ LC/RD that was available in a 105mm. I much rather the air cooled RD rod in 110mm.

For the RGV with a 105mm rod the TZ 4DP piston is best. The YZ runs the ring end gap on the bridge between the B and C ports and I don't like that for several reasons.

[F5 Dave]

Hi Rich

We have been using original RGV rods centered in the piston boss and regularly rev them to 13k plus. I recall hearing somewhere that if the rod has to much side play it can vibrate and eventually break.

2T thanks, its interesting to hear that the 5mm longer LC rods are OK to use.

We also use early 56mm Wiseco YZ pistons.


The YZ Piston Crown Height as measured from the centre of the pin to the top edge of the piston is 0.4mm shorter on the Flat Top 1993 YZ piston (629M) than the RGV and the Domed 86-88 YZ piston (559M) is 0.6 (aprox) taller than the RGV.

So you are using WC pistons in an Air cooled engine? Thought the idea was the AC pistons had more taper to cope with more heat expansion. No issues there?

[richban]

Sorry, yea I know now the 22 has cartriges,but what I was trying to point out was that even with trick shit SP forks revalved with Ohlins stacks etc
all that would be a waste of time unless the chassis geometry was corrected to something like decent numbers we all know about.
And the fact it costs virtually nothing to get those numbers, easily, why would anyone go ahead and spend up on the suspension before fixing the chassis for free.

Yep. Thats is why I am going to fix the chassis first. Thats what I have been on about from the start. I am usually misunderstood.

[richban]

You can get 65hp with just bolt on bits and an ignition. However, you will run into the problem of the shit RGV piston which at 65hp is at their limit. The pin boss will disintergrate and take out the cylinder on the right that or the tang between the arch will break off.
A YZ125 piston is better to use, cranks are easily rebuildable and you use a DT or LC 125 rod for big improvement over standard. We change them to bottom guided thrusts good to 12,500 now.
Free hp available in keeping coolant temp under control which run over 70deg.
Been using Nitron rear shocks which tick all the boxes.

Cheers For the info. The bikes I have ridden so far had stock temp gauges and I was wondering what the actual temp was the whole to I was riding. Another easy fix. I am going to use wossner pistons coz I know a guy who knows a guy.

[mr bucketracer]

FXR's are awesome, no doubt.
But don't be too discouraged, the fastest rider in Wellington is on a 2 stroker. If he makes it to Taupo for buckets that would be real interesting.

So like you say, it's not so much 2 vs 4 or how much HP, it's the quality of the rider, and Wellington has the best riders.

no no the palmy boys

[Forgi]

The glued and screwed in port floor dam held up OK and the dyno results were better.

Attachment 285043Attachment 285044Attachment 285045

Raised port floor Blue line.

Attachment 285042

But I wouldn't read to much into it as this triple exhaust port cylinder made much better power before I "improved" it.

Attachment 285046

All I did was tidy up around the inside of the main exhaust port area where the side ports converge and after I had finished that I found that some of the horses had bolted.

What was a stable of 29 became less than 20 ??????? ...

Originally the the exhaust timing was 203 degrees duration, lowering the cylinder to 200 exposed the bottom of the exhaust port, the floor dam fixed that.

I was also going to try a power valve like piece in the top of the port but in the end a glued solution was not going to be satisfactory in the long run.

Messing with this has held me up so I have switched to working on fuel injecting a known good single exhaust port cylinder. I will try making another triple exhaust later.

Ok Wob, I got it, I've just thought that maybe...

Teezee! It's a pity that you haven't tested the port floor dam held up before the improvement when the engine was stably 29 ps.

If you have any further result I'm interested!

[mr bucketracer]

Got my cases back today, they have been bored for the RGV cylinder.

Attachment 232931

Cylinder fits Ok

Attachment 232930

The position of the reed block.

Attachment 232928

Speedpro told me there is a nice little curved ledge inside the cases that is just right for the reed assembly.

Attachment 232929

So the reed should fit Ok

Attachment 232927

Now I have to make up a spacer plate and reed block assembly, how hard can that be???.....

did you ever finsh this engine rob ?

[TZ350]

Teezee! It's a pity that you haven't tested the port floor dam before the improvement when the engine was stably 29 ps. If you have any further result I'm interested!

Yes, I didn't realy think about it then, but when I get the new triple port cylinder done, a floor dam will be something I will try.

did you ever finsh this engine rob ?

No the 100cc H2O project got shelved when I hit 30hp with the aircooled.

Sure a 100cc H2O might be better and maybe races can be won on low 20's hp, Nat D has done it, but personally I would need miraculous assistance myself.

For now, it interests me to try and push the 125 aircooled with its class 24mm carb restriction out to a reliable 36rwhp.

And I have ideas about how I can do that, but it all takes time.

[twotempi]

did you ever finsh this engine rob ?


If you knew TZ350 you wouldn't ask this question !!!!

[RomeuPT]

Ok Wob, I got it, I've just thought that maybe...

Teezee! It's a pity that you haven't tested the port floor dam held up before the improvement when the engine was stably 29 ps.

If you have any further result I'm interested!

Me too.
Teezee I understand you screwed in a piece to raise the port floor, but glued? What you mean? You used some kind of epoxy? Have had used high temp epoxy for two times in the exhaust port, but the epoxy burned out of shape after half an hour of riding

[TZ350]

Me too.
Teezee I understand you screwed in a piece to raise the port floor, but glued? What you mean? You used some kind of epoxy? Have had used high temp epoxy for two times in the exhaust port, but the epoxy burned out of shape after half an hour of riding

Yes, high temp epoxy to seal the plate. I fastened the plate in with screws, the epoxy was mostly for sealing around the sides and under the plate.

I did not expect the epoxy to last long, but hopefully long enough to get some meaningful dyno runs. I did about half an hour, 10-12 runs and it held up ok. The last two pictures were taken after the dyno session.



If I go there again I will take more care making the plate a better fit and not needing so much sealant.

The glued and screwed in port floor dam held up OK and the dyno results were better. Raised port floor Blue line.

The dyno results were posted here.