ESE's works engine tuner

[TZ350]

Why not completely weld the buggar up then re drill and thread the SP hole and re cut the dome?

I was trying to keep it simple.

I have straightened up a RGV 250 plug in a head I was using, reshaped the chamber, exactly the same compression, and got instant horsepower everywhere.

That is very interesting.

I'm not criticising the toroid; I'm criticising the angled plug. 'Unshrouding the plug a bit more' is not the way to build a winner.

For the sake of simplicity the whole engine is compromised. The basic aim for the team engines was to use a NSR250 cylinder and Std NSR head with a minimum of modification and no porting work at all. A lot of bang for your buck approach .... a 20 for 80 situation.

Cylinder and head modification is basically limited to turning 2.5mm of both. (with a 48mm de stroked crank for 110cc.)

The aim is a good reliable "Team" engine that see's a lot of track time and is easily copied by anyone who might want too.

Now we are trying to improve them with Wobbly's guidance using EngMod.

Head insert ...centralize the plug .... ... I like it but how to do this in an easily replicated way, there will be an answer.

Don't compromise. Sorry if I'm being blunt.

I hear you, and this is an absolutely un compromised (within the limits of my resources) GP-NSR110 engine that is bluntly a pain in the arse and not very easily replicated at all by anyone. With a lot of time on the dyno and not much track action.

But it is totally fun though, I love it. It is a "rainbow engine", where you just know there is going to be a big pot of gold at the end of the rainbow.

[philou]

the JC22 had longer studs on the top as the JC22 had a thicker head casting.

Studs JC20 42,5 mm
Studs JC22 47,5 mm

[Frits Overmars]

For the sake of simplicity the whole engine is compromised. The basic aim for the team engines was to use a NSR250 cylinder and Std NSR head with a minimum of modification and no porting work at all. A lot of bang for your buck approach .... a 20 for 80 situation. The aim is a good reliable "Team" engine that sees a lot of track time and is easily copied by anyone who might want to. Now we are trying to improve them with Wobbly's guidance using EngMod.

I completely respect your reasoning TeeZee. Having fun is the best argument I can think of. 'Don't compromise' is just the competitive mentality I inherited from Jan Thiel. And I bet Wobbly has the same uncompromising attitude.

[Matt@TYGA]

I had the French ones they were very restricted i remember that bit.
Grumph i think was given a flash drive that i think had them on it?
From what i seen it was like a lot of the different euro makets had different specs.
I think a lot of the euro ones were made in Italy engine parts and all.
the JC22 had longer studs on the top as the JC22 had a thicker head casting.
th bottom stud parrn is the same as i have a 250 cylinder sitting on one here but the water feed is slightly different but nothing major.
I had a good google and i cant find anything at the moment other than the stuff in the TRX project.
Attachment 336768Attachment 336769I had the French ones they were very restricted i remember that bit.
Grumph i think was given a flash drive that i think had them on it?
From what i seen it was like a lot of the different euro makets had different specs.
I think a lot of the euro ones were made in Italy engine parts and all.
the JC22 had longer studs on the top as the JC22 had a thicker head casting.
th bottom stud parrn is the same as i have a 250 cylinder sitting on one here but the water feed is slightly different but nothing major.
I had a good google and i cant find anything at the moment other than the stuff in the TRX project.
Attachment 336768Attachment 336769Attachment 336770
Malossi do a 65mm bore kit and cylinder for them not sure if they have a operational PV
http://www.2strokeparts.de/shop/prod...-nsr-125&SESS=
which would make a 360 NSR twin

I may be wrong, but I recall seeing silly things such as plates across the carb insulator with a hole half the size of the carb, and rumours that the CDI was restricted somehow. But I'm thinking that the cylinders were probably the same for all markets.

The coolant spigot is at an angle compared to the NSR250 and 150, probably to clear a bit of frame or something.

The NSR150 was also designed and built in Italy, using (as far as I know) the NSR125 as the base engine design.

I've seen the Malossi stuff. There's a Malossi dealer here in Thailand and I was considering using the Malossi cylinder a few years ago, right up until they told me the price. Yes I think you're correct in that they don't use an exhaust valve.

I think Polini also had a big bore cylinder for the 125. Slightly smaller bore but had a valve. However, wasn't super interested in going any bigger on the bore without going longer on the stroke too.

The latest thing that I have been told is that here in Thailand, in the "open class" drag racing, the latest fad is using an NSR150 cylinder on an LS125 bottom end, but bored out to 70mm. I have no other info at this stage other than they're using a steel liner. I presume that they've stroked it too, but by how much I have no idea. I'm waiting for the dates to come out for the next race and I'm gonna go along and have a peek.

The Thais do some pretty crazy stuff. Not all of it useful, but definitely 10 out of 10 for effort and enthusiasm. Trouble is that most of their engines tend to explode at least once during the day :-)

[jonny quest]

Matt, you may know this. I see a lot of 2 stroke pipes on the drag bikes in Thailand that are cone pipes with a beautiful bright blue colouring.

What metal are the pipes and how do they get that blue! They look titanium, but I'm assuming they're not.

[wobbly]

I think it depends upon how you look at it TeeZee.
Making a long rod crank, adding a gearbox spacer , making a bigger RV cover.
Welding up a plug thread is a walk in the park - you dont even need to pick up a vernier , just a tig torch.

[Matt@TYGA]

Matt, you may know this. I see a lot of 2 stroke pipes on the drag bikes in Thailand that are cone pipes with a beautiful bright blue colouring.

What metal are the pipes and how do they get that blue! They look titanium, but I'm assuming they're not.

There are a handful of guys building Ti pipes here in Thailand. I know a couple of them quite well. The bluing process can be done on Ti and also stainless. It seems that the people that do it guard the process, but I'm guessing that it's something to do with heat and reaction to oxygen. We had some stainless tubes done just to see how they'd look. Not too bad but the price was a bit silly.

They can even do rather complicated patterns if one wishes. We had some stainless silencers that looked like Rupert The Bear's trousers. Always made me chuckle.

[andra_rgv120]

.....

The latest thing that I have been told is that here in Thailand, in the "open class" drag racing, the latest fad is using an NSR150 cylinder on an LS125 bottom end, but bored out to 70mm. I have no other info at this stage other than they're using a steel liner. I presume that they've stroked it too, but by how much I have no idea. I'm waiting for the dates to come out for the next race and I'm gonna go along and have a peek.

The Thais do some pretty crazy stuff. Not all of it useful, but definitely 10 out of 10 for effort and enthusiasm. Trouble is that most of their engines tend to explode at least once during the day :-)

Honda Nova Dash 125 (same bottom-end as LS 125 ???)
10s sec quarter mile, very impressive

[philou]

the cylinders were probably the same for all markets.

In France a 125 is limited to 15 Cv.

For 125 NSR, the French cylinders are different from the others. English cylinder are better

[jonny quest]

https://www.google.com/search?q=thai...7HNl1PdKfz5BM:

I think it's some sort of acid mixture that give the pipe that color.

Those drag bikes launch hard for such skinny tires!

[husaberg]

In France a 125 is limited to 15 Cv.

For 125 NSR, the French cylinders are different from the others. English cylinder are better

You beauty what forum was that on i tried for about twenty minutes last night with no luck.

[Matt@TYGA]

In France a 125 is limited to 15 Cv.

For 125 NSR, the French cylinders are different from the others. English cylinder are better

A great find!

[Matt@TYGA]

Honda Nova Dash 125 (same bottom-end as LS 125 ???)
10s sec in quarter miles, very impressive

The Dash125 and LS125 are similar, but not identical. The crank for one is different. The drag boys use a modified LS crank in the Dash cases.

I heard a story that the LS engine started life as a Dash, with HRC intervention. Small mods here and there, such as the crank for example. Not sure on the other differences.

I used to have a Dash some 15+ years ago, but it got nicked one night from outside my grotty apartment block. I have two LS's in the shed, but never done more than park them and throw a blanket over. One day I'll dig them out........

[TZ350]

I have a Gilardoni cylinder, and like the NSR125 cylinder head I looked at, the head stud pattern is different and will not fit the NSR250 MC21 or MC18 cylinder. So no easy answer for a MC21 center plug there. Also the NSR125 cylinder spigot is a larger diameter than the MC21's.

These would be great cylinders to use but I have not found it easy to get more of them. Suitable MC21 and MC18 cylinders are much easier to find. The Gilardoni is ear marked for a very trick (no compromises) 100, just waiting on the crank to be finished.

[Muhr]

https://www.google.com/search?q=thai...7HNl1PdKfz5BM:

I think it's some sort of acid mixture that give the pipe

It may be Bluing Stainless Steel (heat treatment)