[Bruce CurtisMember]

New and ADR’d Corey?

GasGas250/300
KTM250/300 exc
Husky 250/300

Non-ADR’d YZ250

[Bruce CurtisMember]

I would love to answer with the down and dirty tech stuff but in reality I am not at liberty to as it is someones elses intelectual property.

And that I respect.

[Bruce CurtisMember]

I dunno if i could say I would do so TB, about making short term profit from consumables I almost reckon if i had influence in a large M/Cycle manufacturer I would be pushing MY own barrow, which just so happens to on many levels to make good long term business sense.

I reckon KTM will be the first to bring one out that is workable, some others may bring out half-arsed versions like Bi-moto did with the V-due, but KTM will have theirs well tested before release.

[Bruce CurtisMember]

LC4skin wrote:

Krusty wrote:

So why is it these high tech machines are over heating in the first place? could it be they are not designed for tight gnarly single track? Just curious as it seems odd to me that a 14,000+ machine would overheat.. Is the manufacturer really designing for a race type situation like a4d, safari etc?

Cheers…

There is no problem with the bikes or radiator design the rider just has to go faster in the tight stuff (just like an enduro racer would) creating more ariflow, they are after all enduro race machines not trail bikes

I will beg to differ LC4, they are not fit for purpose in this regard, as the race ones used in the extreme enduros have modded cooling systems for just this reason, and they are sold with ADR compliance, so obviously not closed course comp only…

[Bruce CurtisMember]

This is a back to the basics issue.

Why do we have cooling systems?
what temperature is best for the longevity of the engine?
What compound is best to conduct the heat transfer?

The obvious issue with KTM and their incessant boiling is lack of hot country testing, the colling systems are not designed for Australian/African/ Middle eastern conditions, weather this be insufficent capacity or airflow, or the pump and base circulation systems are poorly developed.

We can overcome these shortfalling heaps of ways if it is borderline ok, bigger radiators which are from an engineering point piece of urine to do. Improved heat conductivity through the transfer medium therough modern science there may well be a better compound than H2O, however what most of them achieve is to raise the boiling point and is this really conducive to engine life?

Modifying the pump for better flow

Re rerouting the flow patterns altogether, funnily enough we have an esteemed member here somewhere who has achieved this although I haven’t felt his presence for sometime, is right on top of this method…

another area to consider is trying to take the heat away through the lubrication system, like the highly sucessful 87-92 Suzuki GSXR11s did…. big HP (over 2oo hp in some cases) under race conditions using nothing but oil to transfer the excessive untapped energy caused by the combustion process….

[Bruce CurtisMember]

Congrats to Mrs STM and the new member of the STM riding clan.

Obviously You do deserve some of the credit STM after all you did have a hand in this … but seriously good stuff.

Time to start hunting for a MA50.. woohoo

[Bruce CurtisMember]

Dennis the Obviously Monikered me ole KTM flogging, back breaking, other person electrocuting, Victorian Brother from another Mother…
same goes…

Me good as gold, having fun on the big Vee, haven’t started the warlock in 3 months, but due to be fired up this weekend for a scoot with the boy wonder and get my arse handed to me again by a ten year old….:blush:

and hows the world of Menace treating you?

Anyway did a lot of reading last night on high pressure DI for 2T dirtbikes, yes it can be done, and yes some roadbikes have been retrofitted sucessfully in prototype.. however even a roadbike is a far different world to a dirtbike, herein lays the issue, the mapping and sensor relationship alone for a 2T dirtbike is a big job for R&D…..
BUT within a few years it will be so, I liken it to the 4T inj evolution, mid-eighties GPZ11 had FI, yet when did it finally arrive on dirtbikes? over 20 years later no less.
like the man says, when the market (Us) start demanding stuff, then and only then will the manufacturers listen, if we don’t they will push us down the path THEY want us to head for the best return on their investment, which at the moment is high maintenance, return business 4Ts. I liken the new Jap 4Ts to the good old cheap printer deals, buy the printer for next to nothing, they make the dollars out of the consumables…..

If we had a low revving (say 9k rpm redline) large bore 2T with a wet sump and High pressure DI and air inj, variable intake timing and ign, there would be a huge rush to this trpe of powerplant, same power for less CCs, far less fuel usage, no need for big tanks, redesign of bike styling more suited to ergos and handling, lighter weith motors, so you can put weight where it may be needed, the possibilities are myraid and mind boggling…..

Just hope we are still of an age to ride them…

[Bruce CurtisMember]

Reality is the smaller players at this stage have no real pressing need given the global sales climate to spend heaps on R&D for this YET.
My understanding is while DI does work, and it works on outboards and skiddos, it is not as good in the world of constant on/off, partial throttle requirements of a dirtbike, we spend so little time at anything remotely resembling a constant venturi signal, the delivery needs are so complex that while it can be done, the money needed is prohibitive.

The boyeson designed trapping valve will also be obselete when the boffins come out with the injected 2T dirtbike engine… put simply, there will be no overlap and unburnt mixture escaping, however if this happens I do wonder if a pressurised air system will be necessary as well?

a large bore low revving injected 2T with oodles of torque and lightweight…MMmmmm

[Bruce CurtisMember]

Evil Rudy wrote:

Nope its just some guys with old bikes are to precious, and they don’t like it when people get sick of discussing the merits of the different white paint used by Yamaha on their early YZ tanks.

Thats why I like the guys and gals here. Real bikes getting ridden by real people.

Rudy
xxxooo

hello Rudy, would it be rude to ask if i may indeed refer to you as “Mr Evil” ?
and I am pondering if indeed you are our new Dick?
The old Dick is still about but he’s been hibernating for a stretch now……….

May i also ask does Tony Abbott really think he will ever be a real man?

Bruce Cee

[Bruce CurtisMember]

every so foten I give blood, am the universal type so everyone get’s a go at mine…

I always reckoned i had too much of it anyway.. always trying to come out of me through various punctures and wounds…….:S

Anyone else here reckon you feel heaps healthier the next day?

[Bruce CurtisMember]

micknmeld wrote:

Sweet ride Bruce. A mate of mine has not long bought one of those bikes and had one of the clutch spring bolts come loose and cause all sorts of mayhem in his motor, when it caught the clutch cover housing.

Hey Michael long time no talk brother… I totally get the veetwin thing now.. you can slap me around next time i dis the twins if ya want…..
Your mates clutch issue that’s an unusual one.. sounds like dodgy apnnerwork somehow.. but Cool if it cut a perfect circle he could attach a piece of pexiglass and have a see through clutch housing.. they’re supertrick.

these big girls only have one known issue of failure..Camchain tensioners spit it, they are a generic one that is used on half the hondas built, but because of the long pause between tension on the cam lobes and the vibes they are not happy in the VTR, mine is showing the signs after only a few thousand kays since replacement. Bought it from a kawasaki dealer.. apparently his own bike has a little suspension tweaking done, but for my fat ass it needs new fork setup but that’s about all.

Just get on hit the button and you’re gone…..

hasn’t got the ugly bellypan anymore either god awful ugly thing and weighs not much more than a fully kitted KLR650 either.

The MOJO is back too……

[Bruce CurtisMember]

Hey Jimbo…woohoo finally someone both older than me and been riding longer than me..I need a mentor in my middle-age… actually just between you and I Jimbo.. lots of these young blokes on here could use a bit of a pointer into the finer arts of appreciating older bikes and real style too……..

welcome to the bullpen and long mayeth you contribute compradre’

[Bruce CurtisMember]

Thanks Laddies.. missed you motley mob too… I Told TB earlier this year I bought a honda,was a long silence on the phone…….:whistle: think he thought I was pulling his midlle stump…. anyway been having hassles getting to log onto the site due to work internet screening and incompatability issues with my home system for the last few months.. anyway all fixed…

I bought a booming Vtwin roadbike, a nice ole VTR1000 so I could do some summer riding and get back to riding to work everyday, the YZ has hardly been used over the summer, between the cyclonic rain and then humidity so dense I needed a pair of scissors to cut throught the bush it’s been a lean summer for the dirt in the Cee household.. but i hear the local lads are amassing at one of my favourite bits of forest soon so time to show my age and fitness again…

here’s the badbike in question

Big cams, modded exhaust, jet kit and crap K&N filter (they run like a hairy dog with too much filter) a bag of torque, monos with a flick of the wrist and no toetapping dance routines on the highway.. just get it into a top and lope along with a distinctive booming note, only got 105 geegees but still covers the 1/4 mile in 10.5 so all torque and little rev shreds rear tyres alarmingly quick, all in all the complete opposite of my previous roadies in engine charactersitics and the warlock… must be getting old

Bloody 4ts already had to buy a set of APE camchain adjusters for it

[Bruce CurtisMember]

is that sorta like grinding the old joining link off your chain and then discovering you can remove and replace chain in one piece?

[Bruce CurtisMember]

Come On Tb you already knew of those bikes didn’t you/

Old hat, the engineer who was championing the 2T cause from within honda came up with heaps of good stuff, and it is all sitting on the shelf at HONDA R&D now as he was moved on to rear vision mirror design or the likes.

Re: the outboard thing….MMMmm

Not quite right there fellas, as Skidoos and personal watercraft have passed the emissions tests, it’s called a trapping valve, and the DI system is a ultra high pressure high volume short sequence jobbie that squirts just prior to ign……

But it is nice that TB has shown himself to be a closet 2T man.

Anyone else wanna come out of the closet now?
Boony I’ve long suspected you, and you too Mick don’t be shy…

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