KTM 450 sxf lunched

[barty5]

so you're up to $550 so far, without rings, bearings, shims, and whatever else wears out on a 4 stroke top end

yeh but its good for 100 hrs how offten you doing piston and rings??

[Rupe]

yeh but its good for 100 hrs how offten you doing piston and rings??

I'm good for 100+ hrs, apparently.
But I don't have an hour meter so who knows how many it did last time.

[B0000M]

yeh but its good for 100 hrs how offten you doing piston and rings??

well you got me there.

[tommorth]

I rekon its about even parts wise provided you dont have a major failure on a fourstroke if you can do the work yourself its no big deal
4ts use less fuel and dont need premix
a mate has an 07 yzf250 that he rapes all the time its probly done 200hours still going strong he did the piston and rings at 100hours needed clearances adjusted on 2 valves reckons the piston looked like new

I still prefer 2 strokes though just for the sound when they come on pipe and the smoke stream stops you geting lost lol

any other dealers nearby that might time you cams for you?

reckless my parts quote was from ktm was near on 3500 and there where a few things that weren't included around 2k of that was cylinder and pipe which can be shrunk a lot by replating

[secondfield]

yup that was rings too.. BTW., very close.

[xwhatsit]

Well what bloody stupid place to put a crankcase breather. Had it been modified? I thought bikes like these were sorted so they could go underwater right up to the top of the airbox?

[kezzafish]

Agreed, it comes out at the level of the crankshaft and goes down through the swingarm with the rest of the waste pipes from the carb etc. The whole pipe wouldn't be a foot long. and because of the hollow crank and sealing system it makes those parts extremely expensive. Austrians are retarded. I'm sure the exc models are much hardier tho. I don't know about RMZs etc bot the yzf450 breather comes out of the cam cover and my mate who rides one rode through that same puddle that killed my bike on his! End of the day you should buy enduro bikes for bush bashing but i don't want to pay all that extra money for a road kit and a bike that's heavier with shit i don't need like a kick stand and a headlight

[secondfield]

Yeah the RMZ comes out of roughly the same place too. Shes an m'xer as well.
I have seen some breather pipes with a tapered end, that squeezes closed with a small slit in it to prevent crap being sucked back into the crank.

[theblacksmith]

I have an old kdx250 (93)- im upto 96hrs on a wiseco piston - bore is still original Nikasil - heaps of compression still.Bikes been totally submerged (Waiouru army ride river crossing).Took air cleaner out and squashed water out.Lifted bike up onto rear wheel to drain water from expansion chamber never took plug out even(no spanner)- kicked the fkn thing a few times and it started and pissed out water from every pipe I could see.
Gearbox oil took on the appearance of soy milk.Rode back to base no probs and did another two loops freezing my bollocks off in wet gear.I went down there to have fun not a great big parts bill.Probably done another 18 trail rides since then.Long live 2 smokers.Especially green ones.New Wiseco piston kit and gasket set - $280 and 3 hrs of my time.Cool.

[secondfield]

Hey kazzafish, was that 'puddle' up the back of karapoti at the top of the pines? just before you come back onto the main track.The bike deep,water filled rut that gets ya every time... Its taken me 3 rides to come through that without bogging and stalling..

re the big four's. JE rebuild kits are sweet. A full top end, high performance rebuild kit for around 500 bucks. Includes forged piston, rings, gudgeon, stainless valves, springs, shims plus complete gasket set required for re-build. Good value. I got a 12:8 comp piston in my RMZ.

Austrians aint retarded thats for sure. The engineering that goes into a kato is pretty damn well thought out. The exc's are a piece of work for sure. Even got a little magnet on the sump plug to catch bits of metal that may otherwise find its way into the rest of the engine. Attention to detail. MX'ers generally arent expected to be stalled under three feet of water! Oh maybe some Austrians are retarded ....the inbred ones who like to lock their kids in basement's etc etc...
But even then they could hold electrical engineering dgrees..


http://www.trademe.co.nz/Trade-Me-Mo...-172447214.htm

Still love those big four strokes ... sound like hell on wheels, traction for africa, more forgiving and less tiring to ride than a two poker (for those of us who arn'et Juha salamen), they will get you where you want to go with a minimum of clutch slipping, wheel spinning, plug fouling gas guzzling antics.

The RMZ actually feels like a two stroke to ride, it reminds me of my old 490. (a couple of mates have said that too).

So whats the plan with the kato? you getting it sorted yet mate?

[kezzafish]

Hey kazzafish, was that 'puddle' up the back of karapoti at the top of the pines? just before you come back onto the main track.The bike deep,water filled rut that gets ya every time... Its taken me 3 rides to come through that without bogging and stalling..

So whats the plan with the kato? you getting it sorted yet mate?

Yeah, that sounds like my puddle. In the clay shit, good fun.
The pumpkin has to be going in 2 weeks for pumice blast or else i'll go mental. I'm doing a super rough jobbie, gonna stick the barrel back in now thay i've given it a once over with sand paper, put in a JE piston like the one you mentioned, re use valves, got a new cam shaft and i've got an engineer doing some dodgy trickery with the ceased head, new gasket set, clean out the sludge, re shim and ride it, then trade it. What ya think of that idea?

[crazyxr250rider]

Sounds Budge, do it right....... how bad are the cam galleries???? at least get the barrel re plated or sleeved try the price for aftermarket valves and crank.
never take short cuts it always ends in tears........

[barty5]

Yeah, that sounds like my puddle. In the clay shit, good fun.
The pumpkin has to be going in 2 weeks for pumice blast or else i'll go mental. I'm doing a super rough jobbie, gonna stick the barrel back in now thay i've given it a once over with sand paper, put in a JE piston like the one you mentioned, re use valves, got a new cam shaft and i've got an engineer doing some dodgy trickery with the ceased head, new gasket set, clean out the sludge, re shim and ride it, then trade it. What ya think of that idea?

note to self dont buy bike from you dodgy dodgy

[crazyxr250rider]

Like I said it would only end in tears.... but not for him......

[kezzafish]

Sounds Budge, do it right....... how bad are the cam galleries???? at least get the barrel re plated or sleeved try the price for aftermarket valves and crank.
never take short cuts it always ends in tears........

The barrel is not too bad and the valves aren't bad at all, companies and people hype the maintenance shit over the top because it covers them and makes them more money. A bit of common sense must come into play. Aftermarket valves and crank have been impossible to find and there's nothing wrong with the crank. I plan to replace the bore after pumice blast, it's just that i don't want to wait any longer. Riding is the reason i go to work every day and if i go much longer without riding i will slit my wrists (joke) the head suffered the major damage and i'll probably end up ordering one of them too. Re plating is not that cheap (around 600) when i can get a brand new barrel from the states for 800 and continue riding my bike on a dodgy bore until the new one arrives. The barrels on these bikes aren't sleeveable because of the wall thickness (thinness). the underlying point here is that all bikes (especially the late model ones and double especially the mxers) are time bombs the amount left on the timer is all that varies