ESE's works engine tuner

[mr bucketracer]

I am all for it ... min 250kg Bike plus Rider in their kit and over 65's get a head start..... Attachment 294965

i would say 99% of riders+bike would be under 200kgs , so a 200kg mark would be the go (-: , yip 65 and over a 1 lap head start per 10 laps would be a fair go

[TZ350]

Having had a lot of fun on a borrowed F5 bike at Tokoroa I thought I would finish my own one off and get out there. Single exhaust port, so not expecting to much and if the carb is to steep I will swap to a pumper. But at least this one should have decent brakes, the one I rode at Tokoroa had virtually nothing and when it got hot there was an enormous hole in the mid range carburation. Made it very hard breaking down hill into the hair pin and then climbing back up the winding uphill bit to the front straight.

[wobbly]

Dont think the idea of an advantage for old guys would actually be fair at all.
Put the 70 yr old Discombe on a good bucket and he would lap most of the field starting from the back.

[wobbly]

That carb will for sure flood under brakes TeeZee, get a D slide downdraft off a RGV F3 or something.

[F5 Dave]

Cut the inlet off & start again. What looks good on the bench is too steep in the bike. Don't ask how I know.

Dowel the head, they move around too much and important with such little chamber. Don't try weld into the head. They get super soft & will warp like crazy unless you heat treat them.

[mr bucketracer]

a 28mm kr250 carb is the way to go

[TZ350]

a 28mm kr250 carb is the way to go

If anyone can sell me one, I would try it.

Plan B is to use a 24mm Tillotson pumper or get one of the carbs Yow Ling posted a picture of.

[husaberg]

If anyone can sell me one, I would try it.

Plan B is to use a 24mm Tillotson pumper or get one of the carbs Yow Ling posted a picture of.

The KR250 or the TZR250 both had the Down Draft 28 mm Mikuni.

[WilDun]

Dont think the idea of an advantage for old guys would actually be fair at all.
Put the 70 yr old Discombe on a good bucket and he would lap most of the field starting from the back.

So it is Trevor Discombe! - I remember he was NZ 350 champion ( on a Manx Norton) way back in 1966 when I first arrived in NZ, I nearly bought an old AJS 7R he was selling on behalf of someone but I thought the better of it as those bikes were being replaced by two strokes and I was always a 2 stroke fan. (ended up with a Suzuki)
I also remember him going for a skate just over the railway just before going through the graveyard at Wanganui, ending up in a heap, out cold! - I would say he had a sore head after that one.
Good on you Trevor for sticking at racing, do be careful though!
Will.

[F5 Dave]

If anyone can sell me one, I would try it.

Plan B is to use a 24mm Tillotson pumper or get one of the carbs Yow Ling posted a picture of.

Can do better than that, Yow sent me a pair for giggles, I might still have them & could send them on. . .unless I gave them back. Were like 27mm Keihins from some flavour NSR. Sold my last 28 Downdrft mikuni to Tim I think.

Er hold on that is a downdraft Mikuni, only 15 or so degrees. Cut it off & start again but flatter & shorter.

[husaberg]

Can do better than that, Yow sent me a pair for giggles, I might still have them & could send them on. . .unless I gave them back. Were like 27mm Keihins from some flavour NSR. Sold my last 28 Downdrft mikuni to Tim I think.

Er hold on that is a downdraft Mikuni, only 15 or so degrees. Cut it off & start again but flatter & shorter.

Another idea the MVX250 had 24mm downdraft Keihins they were for a 80cc cylinder
They look like they could be bored out as well as a nice downdraft.Looks about 45 degrees.......

Try Drew or White Trash for some...........Alll the attachments are MVX250

---

Anyone know what the NS400R ones look like?
Latter I googled and they look like the NSR250 ones only 26mm
(links are all NS400R)
http://classicracereplicas.com/prod6...4&#prod_anchor
http://www.fastlineparts.com/media/c...s/dscn7828.jpg
http://www.fastlineparts.com/media/c...s/dscn7831.jpg
http://www.fastlineparts.com/media/c...s/dscn7825.jpg

[wobbly]

NSR400 carbs look the same, I have access to a bunch of those, will get one and see what size it is.

[F5 Dave]

Oh yeah, when is Jared going to get the spark & pingas to finish that bike?

I have an MVX carb as well. Seems to measure 25mm. NSR ones at 27. I'd believe my expanding calipers and vernier before google. . . Not to say I wasn't shaky transferring the measurements, but I was pretty keen for the MVX to be 24mm to be legal for aircooled 125 at the time & I still couldn't convince myself they were.
MVX carb yours if you want it Rob.

[husaberg]

Oh yeah, when is Jared going to get the spark & pingas to finish that bike?

I have an MVX carb as well. Seems to measure 25mm. NSR ones at 27. I'd believe my expanding calipers and vernier before google. . . Not to say I wasn't shaky transferring the measurements, but I was pretty keen for the MVX to be 24mm to be legal for aircooled 125 at the time & I still couldn't convince myself they were.
MVX carb yours if you want it Rob.

I too would believe your calipers over Google too, Dave
But remember the GrandLord Satan the owners of Keihin, Measure the carbs in a way that they decide and i guess in the case of Keihins it is at the venturi.
I think there is about 4-6 different sizes for the NS-NSR250 carbs. Most i have seen are an oval like the XR200's.
I am begining to think they may all be based on only a couple of body sizes.The ns sites list them by they model numbers like TA09 etc
According to all the dyno stuff i have seen the NSR Keihins actually flow bloody well considering they are a STD production carb.
But they don't have the needle section and adjustability of the others......
I have a couple here (from Rob) off a NSR250 and they are about 32-34mm at the throat.

There is also another new downdraft Mikuni alailable in a lot of sizes based on what looks like a tmx you see them for pitbikes and so forth can't remember what they are called.(latter TDMR)

[F5 Dave]

yeah those are probably ideal for my (super long term project) Stinger when I finally decide 'screw the misty-eyed std restoration idea' & tune the crap out of it instead.