ESE's works engine tuner

**husaberg** · 7th December 2011, 19:27

Originally Posted by 2T Institute

And it has a balance shaft.
Will look forward to see what happens with it.

The balance shaft or the engine?

Originally Posted by 2T Institute

A KH 125 can easily accomodate a water cooled cylinder, ,my own 'top secret' project for the Aussie Nats will be a YZ85 (in TZ125 frame) with a 'mini RSA' pv cylinder

My idea is to use as many std parts as possible so it can be easily replicated by all if they so desire and it is ok with wob.

But I love the way your thinking. How many other tuners are so freely giving advice for four stokes like we see here.

we are lucky and honored to have access to some of the best 2 stroke minds in the tuning world
It seems the Four stroke guys spend an awful lot of time here after all as well.

Wob has helped out the odd four stroke as well so he isn't that biased i seem to recall a blue red and pink one that did all right in the 90's

I have a few ideas floating around on how to bring the MB100 into at least the 90's rather than the 70's. In kind of a kit form.

But it would be nice to see some more info shared on this for the good of all the others about.

Rob is already basically doing it now with the GP125.

**wobbly** · 7th December 2011, 19:55

Not wanting to make excuses but the reason Nigels bike was unreliable was that he rode it for a couple of years with no issues at all winning plenty of races..
Then it started seizing regularly.It was the fact that the bridge had 3 times the proper clearance,from ring wear.
He now has had the bore plated, the bridge ground and a new piston with oil holes.
It hasnt been fanged in anger since all that work, due to him having a back op and his work/time issues.

**2T Institute** · 7th December 2011, 19:57

I'm not letting to much on at this point as Buckets here are quite different to NZ.
Oh also there IS a modern rotary valve engine that by a quirk of fate has a odd ball 51.8mm stroke the humble 1982 Kawasaki AR125. Water cooled, 6 sp rotary valve ticks all the boxes hoping to get it legal for Period 5 but would make an ideal bucket engine.
I see the scans are backwards and 6 is missing.

**koba** · 7th December 2011, 20:22

I've always done alright in GP's considering having a huge power deficit.

When I sort some horsepower I'm keen to rack up a few more good placings on my two stroke.

**husaberg** · 7th December 2011, 20:44

Originally Posted by 2T Institute

I'm not letting to much on at this point as Buckets here are quite different to NZ.
Oh also there IS a modern rotary valve engine that by a quirk of fate has a odd ball 51.8mm stroke the humble 1982 Kawasaki AR125. Water cooled, 6 sp rotary valve ticks all the boxes hoping to get it legal for Period 5 but would make an ideal bucket engine.
I see the scans are backwards and 6 is missing.

Glad to see i am not the only one who encounters problems with the order when posting attachment they seem to just go in random order no matter how they are loaded sometimes.

The quirky stroke is the same as the KH100 mmm....

They were tuned extensively in the UK for some racing class

I posted a link awhile back to a guy that specialized in them somewhere there was a crowd who used to specialize in tuning them and the later AR50 and 80's.
Peterborough? and BDK race engineering I think.

It also would qualify here for post classic racing.
I never knew they were rotary valve plus reed like a KR250 though Thanks for the info.
But it does tick pretty much all the boxes if it had a proper power valve.
The engine to be used for Vanessa is at least three generations more modern.

She looks a little like this below.

**F5 Dave** · 7th December 2011, 21:04

Originally Posted by husaberg

. . .
It will please Dave in that it is a Honda. . .

Let it be widely known that I ground the letter H, O, N & a few others off the side of my MB engine case. Over 16 years ago.

**F5 Dave** · 7th December 2011, 21:10

Originally Posted by TZ350

....

Not sure why Nigals has had reliability issues, the team ESE bikes have finished plenty of long track races and proved quite reliable, some are making a few ponies now and still seem to hold together ok, . . .

He'd said when he had an EGT running the bike on a long track the temp was shooting up to a silly level. He changed the needle jet & it stayed constant where he wanted it. Needle jet restricting the main. That's why it did fine on kart tracks & seized on long tracks.

**F5 Dave** · 7th December 2011, 21:15

Just got back from Sketchys place. This is a YZ100 piston from Evilbay with two simple shrouded bushes. The pin is shortened so it is long enough to push them into the circlips retaining them & not rubbing on the bearing. They are made pretty tight but sliding. Far better than I could hope to turn up on my lathe. By a long shot. He can make some nice stuff.

Peg seems to be out of the way & ex covered at TDC. Deck is the same as MB, but you can't have everything.

I'll try put it in before the meet on sunday. Only drama is the piston crown is lower & a different profile from the MB one so com will be lower & squish will need adjusting. Not sure if I'll have the time.

Thanks Glen.

**husaberg** · 7th December 2011, 21:25

Originally Posted by F5 Dave

Let it be widely known that I ground the letter H, O, N & a few others off the side of my MB engine case. Over 16 years ago.

Well Da......

Was it due to this

Originally Posted by Soichiro Honda

こんにちは、特別なデイブ San あなたが我々がフルの音階と上塗り教育までそれから（彼・それ）らに送った写真の回転を提案して、そしてした（とき・から・につれて・ように）、我々が正確に鈴木ピットの前（に・で） mr ガードナー Sans 移動住宅を駐車したという重量分配に関しての内報をありがとうございます我々の自転車フレーム我々が、あなたが我々がデイブ San であったと言ったのとちょうど同じ（ように・時に）、エンジンの下の燃料タンクとそれの上のパイプで重心を下げようとしている間違った方向に入っていたように思われます。

Hello Special Dave San

Thanks for the heads up regarding the weight distribution. We parked MR Gardner Sans motor home in front of the Suzuki pit exactly as you suggested and took rolls of pictures. We then blew them up to full scale and overlay-ed our bike frame. It seems we were going in the wrong direction trying to lower the Center of gravity with the fuel tank below the engine and the pipes above it just as you said we were Dave San. We think with that info we should be able to reclaim the titles from that dastardly Yamahas We now look set to dominate the gp racing scene so thanks for the tip also thanks for the heads up on that young Doohan chap.Well he’s looking to be going rather well now don’t you think. If we can keep him in one piece and in a couple of years i think he will do OK.
On a sadder note that young chap Neil you recommended for the job in the design department has left on a rather sad note. After his initial success with the VF750 cams.the VT250 cam chain tensioners and the MVX rear cylinders we had a bit of bother with him and had to let him go we suggested the honorable thing was Hari Kari but I hear he is now tuning scooters in Europe so the punishment will fit the crime as you westerners say.ha ha
More bad news as well our people in the racing department are a little concerned to here you are intending to modify one of our commuter bikes into a race bike. I have suggest that you could remove the logo as it would be rather embarrassing for our corporate prestige if we were to be upstaging in the GP classes my one of our own creations especially a humble commuter bike. So could you remove the logo lastly thanks for the invite to Taupo for the world debut of your new creation but due to my frail health i will no longer be able to make it. Although i am keen to know how you get on. Keep me posted. I hope to see you in Suzuka in 92.
Soichiro H 1/4/91.

**TZ350** · 8th December 2011, 05:36

EngMod2T

Click image for larger version.

Name: Nozzels.JPG
Views: 164
Size: 128.1 KB
ID: 252240

I was trying to explore the effect of various nozzels at the exhaust port, thay are all 34mm and vary in the exit angle and length.

They started at 5mm long out to 30 mm and the angles varied from 61-33-22 degree to 11 for the 30mm one.

Now I am not sure if the change in overall tuned length was making the difference or the angle of the nozzel but food for thought.

**dinamik2t** · 8th December 2011, 05:54

Hey, TZ!
I got better results at first with the shorter nozzles, but I ended up trusting Wobbly's experience and left it at 30mm L. Then I tried to accomodate the length added by removing some mm's from where it would seem to matter the least in this testing. I think those points where the straight pipe I have before the header and the exhaust duct length.
I shortened the former by 20mm and the later by 5mm (I do can actually dig 5mm in my duct, due to its shape). I ended up with pretty much the same results of the short nozzle.

**TZ350** · 8th December 2011, 07:25

Originally Posted by dinamik2t

Hey, TZ! I got better results at first with the shorter nozzles ... I tried to accomodate the length added by removing some mm's from where it would seem to matter the least in this testing. I think those points where the straight pipe I have before the header and the exhaust duct length. I ended up with pretty much the same results of the short nozzle.

Thanks, I will try that ...

**wobbly** · 8th December 2011, 08:55

Hey TeeZee, I think what you are seeing is related to the fact that the sim cannot replicate the flow regime that an oval to round transition creates in the spigot.
The wide oval shape, that keeps this width right thru to the header start,really promotes the flow from the top of a T or the tripples in that setup.
But as I said at the start of your experiments I have not tested the relationships or area changes in a single port engine.
My feeling is that just maybe a single port would "like"a small volume duct,and then a step at the header - as your short transitions seem to help top end, at the expense of some area under the curve leading up to peak though.
I have asked Neels about the ideal way to model this as part of replicating a sliding header project I am working on ( as this has a step at the end of the header).
You cant have a "zero length" step within the pipe, so I have asked him what to do.
Will let you know the result.