A crashed Bucket

[Buddha#81:Me]

Buddha, I submitted this before reading your post.
That situation sounds like a bit of a freaky occurrence, quite shit. Perhaps stipulating a 'delicate' pace, out of the way (Nowhere near the raceline) would be a good idea?

To be fair this was at ruapuna, your bikes are set up quite differently u north and crashes are at a slower pace with less energy involved with more crash protection. Do you like the way I'm sitting on the cook straight fence on this one!?!

[TZ350]

To be fair this was at Ruapuna, your bikes are set up quite differently u north and crashes are at a slower pace with less energy involved with more crash protection. Do you like the way I'm sitting on the cook straight fence on this one!?!

I tried to differentiate (probably not very well) in submitting F4 F5 races run on Kart tracks be excluded from the proposed rule change. Bucket races held on full tracks, well that is different.

A variety of opinions is good as MNZ welcomes all input so they can make informed decisions. Check out the proposed rule changes here:- http://www.mnz.co.nz/docs/default-so...1.pdf?sfvrsn=2 its important to submit feedback where you can, there are only a few days left.

[Buddha#81:Me]

The brains trust at MNZ has a bucket influence so I'm sure the best decision will be made.....hopefully......surely

[koba]

To be fair this was at ruapuna, your bikes are set up quite differently u north and crashes are at a slower pace with less energy involved with more crash protection. Do you like the way I'm sitting on the cook straight fence on this one!?!

Yeah, nice work!

[kel]

KT100 pistons are a great idea but (and again I'll repeat it) rule changes can't benefit one group of motor owners over all others. For this year IF the rule change goes through you WILL be limited to a 24mm carb and air cooling.

And so it has come to pass. Bore away boys, just remember the 24mm carb ps we can shorten and taper bore your 24mm carb for a small fee (small just like the carb) .

015 RATIFIED RULE CHANGES – Effective 1st of August 2015
Chapter 24 – Road Racing – Miniature

24.2 - Engines must be derived from non-competition motorcycles. Motocross, Road Racing, Enduro and Go Kart motors (for Husa) and transmission parts are not permitted. There shall be no restriction on the make, type or design of carburettor, ignition, exhaust, piston, cam, valve springs or cooling system except for class eligibility. All engines must be normally aspirated except F4 4 stroke engines of less than 100cc capacity and F4 2 stroke engines of less than 70cc capacity, which may be turbo or supercharged. F4 2 stroke engines over 104cc are restricted to carburation equivalent to a single 24mm carburettor, F5 4 stroke engines over 53cc are restricted to carburetion equivalent to a single 20mm carburettor.

Miniature Road Racing – The maximum capacity for rebored engines shall be:
F4 2 stroke 55 – 110cc

[FastFred]

Great to be able to use the 52mm KT100 pistons but the over 104cc 24mm carb rule still applies ....

MNZ trying to keep it fair for the the 125 air cooled's I suppose and it would be selfish to argue with that.

Still, its great to be able to legally use those cheap pistons and get some more life out of the old 100's. Cheap pistons and no potential big bore performance advantage, the whole thing just looks like commonsense by MNZ to me.

[speedpro]

It's amusing that a 24mm carb is still seen as a restriction. Properly implemented it clearly is not a restriction. Check the ESE thread for confirmation.

[TZ350]

My best Team ESE dyno session ever with the 1980 Suzuki GP125 and 24mm carb.

[jasonu]

It's amusing that a 24mm carb is still seen as a restriction. Properly implemented it clearly is not a restriction. Check the ESE thread for confirmation.

But Mike have any of the high HP 125 2 strokes won anything more than the occasional race (or championships)? From where I sit (10,000 miles away...) it looks like those bikes spend more time blowing up or flicking their riders down the road than being ridden or doing any significant winning. With the 24mm carb restriction these motors have been tuned to be more high strung to produce competitive HP thus more prone to exploding and peakyness. Therefore the 24mm carb restriction IMO is working.

[speedpro]

I don't see it as a bad thing if people believe a 24mm carb causes any of those troubles. Rob's dyno chart is hardly a picture of peakiness.

[jasonu]

I don't see it as a bad thing if people believe a 24mm carb causes any of those troubles. Rob's dyno chart is hardly a picture of peakiness.

Mike what do you think would happen if the 24mm carb restriction for 125 air cooled 2 strokes was lifted?

I'm not sure which dyno chart you are referring to but what are the race results and reliability of that particular bike? What I am saying is the 24mm rule is forcing builders to over stress and over tune the 125 air cooled motors making them unreliable and hard to ride.
I am not ragging on them, this is just my opinion.

[chrisc]

Isn't blowing up and flicking down the road all part of performance 2 stroke development? There's nothing like learning the hard way!

That GP engine certainly isn't peaky. One day when it all comes together we might see its real potential. Until then I have huge faith in the learning from those engine and body failures (ouch kel). team ESE

[kel]

It's amusing that a 24mm carb is still seen as a restriction.

I may well be proved wrong but I think we have pretty much found the limit for power production from the 24mm carb without the aid of a plenum or the like

With the 24mm carb restriction these motors have been tuned to be more high strung to produce competitive HP thus more prone to exploding and peakyness. Therefore the 24mm carb restriction IMO is working.

I'm not sure its the carb to blame for this

Mike what do you think would happen if the 24mm carb restriction for 125 air cooled 2 strokes was lifted?

Even more failures as power would increase further, the air cooling is the true restriction

A reliable 30hp out of a 110cc water cooler would be a piece of cake, its f##k all work and easily the winning option. This rule change is the nail in the air cooler coffin. Next year lets clear the way for an open carb size and finally push the 125 air coolers to the back of the sheds

[andrew a]

Nothing is mentioned about air cooled in the blue . Dose this mean if it is over 104 it can be water cooled an 24mm carb?

[kel]

Nothing is mentioned about air cooled in the blue . Dose this mean if it is over 104 it can be water cooled an 24mm carb?

Up to 110cc can be water cooled, but if greater than 104cc then restricted to 24mm carb.