[AlexMember]

Haha welcome to the KTM Vs Honda battle for the universe.

[AlexMember]

That Skidoo motor is essentially the same as we have been discussing.
Injected fuel. Crankcase air induction with transfer ports. 2T oil delivered to the crank (and the powervalve which is odd). What happens to all the oil? My guess is they are loosing some to misting and splashing in the crankcase and burning it (“Virtually no 2T smell…”). They might be using “better” big end bearings that require less lubrication rendering wet sump overkill?
They might even have a drain/pickup below the crank so with the force of the compression stroke any residual oil gets pushed back into the 2T reservoir?

[AlexMember]

moto wrote:

axel wrote:

Maxxis tyres??

It’s an American bike, they come with different tyres to the shit we get here

I didn’t realise Krusty was in Septic Yank Tank land. Now I get it!

[AlexMember]

Yep slow here too, especially posting. I live far away though

[AlexMember]

Well yes you could but can you imagine the manufacturing process to do that??? Most expensive crank in the world.
Remember that currently there are a couple of simple holes in the top of the rod to let lube get to the little end bearing. Realistically there might not be a great need for lube up there too you know.
Regarding a valve, yes there are working 2T devices that have an intake valve. I’m pretty sure they are still force fed air as there is no way to “draw” air in.

[AlexMember]

Just as you took the site offline last night I clicked send on a lengthy post. Fortunately it did get saved and migrated wooohoo thanks Chris!

[AlexMember]

Maxxis tyres??

[AlexMember]

I have seen home made lowering links for a DT. Trailing links were longer I think.
A Kato 200 is like an F1 car to a DT200 Commodore. Absolute madness. I remember a bird riding an AssGass EC200 with platform soles (some here would have ridden with her too – nice lady). That EC was very much detuned to lug around.
The YZ and DR are interesting choices. One will want to stall constantly and the other will crush her alive when she fell over?? Well I’ve never met Jodie but then again if she is ok with a YZ and a DR the DT200 will be spot on then. The DT200 seat is like a lounge chair that you sit “in” not “on”. You might find it low enough already. Lower the front tubes and make up some lowering links and it’s about the same as a DT175!!
I have a mate in town here that has a DT175. It was registered and ridden around town. The exp chamber was emptied of baffles (DT200 has them too), the carb was bigger and some massaging of the ports yielded a nasty weapon that would bite hard. Very surprising.

Really you’ll be fine with the DT200. There are a heap around still running and at wreckers too. They were a great bike back then. The USA didn’t get them. They only got WR200. The UK, Asia and Europe got the WR200 too but was called a DT200WR which was very similar to the WR200 (steel tank though and even more gay colours).

One of my favourite projects I saw was a WR200 engine slotted into a YZ125 chassis. Electric power in a light chassis. Nice. No rego sadly.

[AlexMember]

Yeah good point. Not sure about that.
They could utilise a special type of 2T oil that does contain something (fuel) to encourage it to transfer and eventually be consumed but I think that defeats the purpose of reducing emissions.
Why could they not run a wet sump of 2T (or really, even 4T oil)? The oil would need to reduce it’s misting so it doesn’t transfer so easy. The cylinder walls need a thin coating of oil for the piston … dripping into the transfer ports ….urgh. Who knows. They need to do without transfer ports, run a wet sump and just force the air in the side intake port like a 2T diesel supercharger style!

[AlexMember]

You sound like you want one of those new ’12 -’13 bikes Rockit….

I rode last Friday at Mullion Creek near Orange. Found some of the old 4Day tracks – ah the bad memories. Fooking freezing. Orange had snow on front yards at midday.

[AlexMember]

Yeah, thanks Moto. PE no way. IT maybe.

Way too optimistic thinking anyone’s wife will ride a DT200 happily. DT175 maybe. TTR250 a stretch.

[AlexMember]

I’m pretty sure it’s a fuel injector as you know it. It will spray misted fuel directly above piston crown. Spark will ignite as usual and all as the exhaust port is closed so there’s no loss.
As for lube on bearings again I’m pretty sure they will use oil jets to shoot at the bearings like your 4T engines do. There’s no reason they can’t design the c-rod and/or gudgeon pin/bearing to accept oil delivered that way. The only trick is to use as little as possible (emissions) as the air is still moving around the crank and using transfer ports. For example: On BDC the crank at it’s lowest you could position the oil jet literally mm away from the bottom end bearing and use something like a timing cam on the crankshaft to trigger it. Same for the top end bearing: squirt the c-rod face on the downstroke so it runs up the rod to the little end bearing. Something like that.
Oil injection pump/tank like a DT/KDX of old would be a given.

[AlexMember]

moto wrote:

I didn’t read the article as I’m just baout to jump on the train home. I did notice it said it will inject the fuel late in the cylcle when the exhaust port is blocked. If this is the case and with the fuel inection being electronically controlled why bother with the expansion chamber?

You shouldn’t need to scavenge the fuel as it’s DI and the sonic return wave in the chamber will only ram exhausted gas back into the cylinder on the compression stroke before the port closes :huh:

Correct.

[AlexMember]

gavb wrote:

The Yamaha WR of the same vintage had very similar running gear.

That’s not entirely true. I have a WR200. There are “some” shared parts. We also share parts with TTR250 bikes too. WR200 is not DT nor is it YZ. It’s a bitsa.

The DT200 community is still alive. I have seen some fine examples of restored DTs on yamahait.com.au

Biggest complaints were always forks and brakes. The shock wasn’t so crash hot either.

The blaster is more related to the WR engine than the DT. Be very careful buying blaster parts. Let yamahait and boats.net be your most visited sites.

[AlexMember]

Yep you should STM. Otherwise it will not stay calibrated. Im speaking of the type in the picture above (barrell type twist the handle). Higher quality bar and pin style ones dont have that requirement.
Never undo the handle all the way with these wrenches as some of them are known to not wirk properly again.
I cant remember the proper names for these torque wrenches. Im having a stupid day.

[Author]

Posts