ESE's works engine tuner

[Grumph]

I searched all over the world for a good priced " real " Devcon,and was amazed that RS product 691-195 was as good a price as I could get.
RS is always silly prices but they have the stock usually,I ordered a couple of tubs and it took a few days to come from usa.
The putty doesnt slump much and can be smoothed over with a wet finger to look real nice without much grinding when set.
If you want to do port roof angles I sit the cylinder on a jig of some sort with the angle you want,warm the cylinder up, fill with Devcon and the temp makes
it slump slowly level at the correct angle.
Put a bit of tape over the bore so you can over fill slightly and then grind the roof angle and corner radius when its gone off.
At 80*C it goes hard in about 1/2 an hour.

The Loctite one is more liquid than devcon and can present problems getting it to stay where you want. I find a dam made of plasticene works well. Cast Iron...historically you'd bronze it. The right flux is available. I have used it to repair fins on Vintage stuff.

What surface prep do you do Wob ? As a minimum I bead blast. In 4T inlets I often insert a pin or screw to mould the filler around - but I'm paranoid about it coming loose....

[peewee]

This is what I understand they used at Aprilia
http://www.sylmasta.com/acatalog/Cre...e_Putties.html

There is also references from other contributors to what they use.

Reference to "Stucco Verde"
on Page 16, 28, and 30 of part 2 of the thread Interview with Mr Thiel and Overmars

i believe thats the same stuff i posted on the previous page, just under a different label name. can find it all over ebay for dirt cheap

[husaberg]

i believe thats the same stuff i posted on the previous page, just under a different label name. can find it all over ebay for dirt cheap

No idea I just remember it being on pitlane....

[FastFred]

It is well known that having water flowing around the entire exhaust duct is advantageous. However, in situations where the duct has too large a volume is it on balance, better to reduce the volume with a Devcon in-fill and lose some cooling effect, or not?
Trevor

Links to posts where TeeZee talks about screwing and gluing with Belzona epoxy a plate into the exhaust port for an exhaust port dam. You will have to go to the original posts to see the pictures.

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

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.

Well at least its good to know I am on the right track but I sure would like to know if this is the limit or if I can take it closer to the top of the transfers.

The exhaust port dam is so easy to impliment it certainly would be worth while looking at it again some more in the near future.

And it improved when I put in the exhaust port

Thanks, but screw and glue looks like an easy repetable way of doing it.
The last one was held in place with a couple of screws, and that seemed to work OK.

Attachment 292539

The good news is, that after 40 liters of fuel and hours on the dyno the exhaust port dam and Belzona epoxy are still there.

[TZ350]

Well that was Mt Welly, my little RG50 ran beautifully, I finished with two third placings in F5.

Nathaniel set a new F5 lap record of 30.249 which would be a very respectable time for F4 A grade.

Fine day, great organisation, friendly people what more could you want.



Speedpros EFI bike was there, I think this is the first ever kit based home brew electronic fuel injected Bucket ever raced, sounded very nice on the track. When Speedpro started it in the pits, he simply pulled the back wheel by hand and it started right up, very impressive.



A couple of the 2T's that run in F4

[TZ350]

I have been mulling over how to arrange air ducting for the Beast MKII to be known as Queen Anns Revenge.

Smitty has made some suggestions to me about using the area between the front number board and mudguard as an air duct. Today I went around the pits and had a look at some of the FXR setups.



It looks like some of the FXR's have shaped front number boards that direct some of the air stream towards the oil radiator above the engine.



The old Beast had a front number board that directed some air down towards the engine and my original GP125 had a duct under the number board that directed the air stream onto the head.

For Beast MKII I will develop the ducting ideas further and have air scoops and ducting on the engine itself too, like Kels number 38.

[chrisc]

Kel's KE125/RS125 air ducting from the 2014 Tokoroa GP. Also one of my favourite pit photos.

Click the photo for larger size

Link to the gallery here



Slightly closer photo:

[F5 Dave]

Because I'm in it? I bet that's it.

[chrisc]

Because I'm in it? I bet that's it.

Close, but it's the matching racing stripe of Kel's hat, his t-shirt and the back of his leathers that make it.

[husaberg]

I have been mulling over how to arrange air ducting for the Beast MKII.

Smitty has made some suggestions to me about using the area between the front number board and mudguard as an air duct. Today I went around the pits and had a look at some of the FXR setups.



It looks like some of the FXR's have shaped front number boards that direct some of the air stream towards the oil radiator above the engine.



The old Beast had a front number board that directed some air down towards the engine and my original GP125 had a duct under the number board that directed the air stream onto the head.

For Beast MKII I will develop the ducting ideas further and have air scoops and ducting on the engine itself too, like Kels number 38.

John Bradleys first book book pg225 on has some interesting stuff on ducting for air cooled bikes.

[TZ350]

Thanks for the tip, looked for the book and found this:-

http://silodrome.com/moto-morini-bialbero/



Great looking racer, and even better looking air duct for directing cooling air to the head.

[husaberg]

Thanks for the tip, looked for the book and found this:-

http://silodrome.com/moto-morini-bialbero/

Attachment 303994Attachment 303996

Great looking racer, and even better looking air duct for directing cooling air to the head.

And so so nearly stole the title from the Honda four.(Hailwood I think was on the Honda too)

[seattle smitty]

Question (my first of probably many here, until y'all get fed up with them):

Looking at some of the photos here, it appears that some are wrapping their pipes with thermal barrier wrappings, which I'll refer to generically as thermo-tape. Another way to thermally insulate an expansion chamber (with its large heat-radiating surface area) is with a ceramic coating. The best-known one of these in the states is done by a company called Jet-Hot. Jet Hot blasts your pipe with alumnum oxide, then coats the inside and double-coats the outside with their heat-barrier/reflectant. Contrast this with the usual high-temp flat black paint most of us have always used on our pipes, a treatment that probably increases heat loss.

As you all know already, the idea of the ceramic coating or the thermo tape is to retain temperature and acoustic wave energy. I have been googling the subject trying to find somebody who has done any semi-scientific (i.e. with a dyno) testing of these heat barriers. Specifically I'm wondering how much the heat barriers typically change the tune of the pipe. Do you end up cutting and shortening your pipe(s), or build entirely new pipes of a different length/shape/angles/etc. to accommodate the effects of reduced heat transfer? I find people asking each other these questions, but not getting much more than speculation, or seat-of-the-pants impressions from a ride around a kart track. I have seen in various hot-rodding and motor-racing forums that some of you Kiwis are on top of the tech. Does anyone know something more about this than a lot of us dumb Merkins with uninformed opinions?

[wobbly]

There is only two main reasons to be using thermal wrappings on 2T pipes.
The first as was done by Aprilia was to stop the radiated heat from getting at the crankcase/gearbox.
Then the second is to reduce the effect of cool air flowing over the pipe and lowering the wall temp.
This is also done by many race teams by having carbon shields over the exposed parts of the pipe hanging out in the breeze.
Another is mainly due to the second one, but as the pipe heat is retained by the wrapping - the effective tuned length is shortened
due to the increase in wave speed - and this can be used to increase the overev power.
But then this really indicates that the pipe is too long to start with.
Bikes like the RZ/RG500 need to have longer pipes on the rear cylinders, as there is no cooling air over them - unlike the bottom ones that
are cooled by air thru the fairing, but also by the air down the sides.
But as there is never a free lunch, the retained heat due to wrapping will maintain that heat over a much longer period and
this then also looses a heap of bottom end power as well.

An unwrapped or uncoated pipe will drop its wall temp quite rapidly on the overun into corners ( titanium does this even better ) and gives
a natural increase in lower end power when getting back on the gas.
All this is very hard to replicate on the dyno - except to say that I have tested several pipes on the dyno with air flowing over them, and the customer has subsequently had them coated
( usually for the visual effect only ) and then reported that the pipe had lost all its bottom end.
After being given stick for doing it wrong, they grit blasted the ceramic coating off the pipes and they responded exactly as originally designed.

Last issue is be aware that wrapping the header up near the flange is a very bad idea - it overheats the return plug of A/F sitting in the duct - and Mr Deto arrives quickly afterward.

[husaberg]

The Nascar style tape wrap allegedly causes TI pipes to rot extremely quickly when exposed to water.
Nascars used to wrap the pipes to stop heat transfer to ancillary accessories such as alternators etc rather than for any go faster factors.

We have covered the different pipe materials have different properties but this graph sticks in my mind.