Took a plunge... trying a PP LXR250 EFI

[BlackBike]

Chonda, I don't remember you having much luck with the f.i. mapping. Is this something you could get to work with the big b. Kit?

[ChondaChondaChonda]

Originally Posted by BlackBike

Chonda, I don't remember you having much luck with the f.i. mapping. Is this something you could get to work with the big b. Kit?

The EFI software didn't let me fiddle as much as I wanted, but it did a spot-on job of tuning the motor. Perhaps I communicated it poorly.

I have *zero* worries that it will be capable of adjusting to the overbore. Especially after seeing how well it adjusted to the massive temperature and altitudes we encountered throughout our Tour of Idaho.

If there are problems I will report on it here.

[BlackAcid]

Ive had the LXR250f for just over one year now and think that kit would be a great upgrade. Only shortcoming for the bike that I have encountered is that it needs a little more power. Did you get that kit through the description in the video? Looking forward to seeing how it works out.

[ChondaChondaChonda]

No, I didn't have the guts to order anything from Russia.

The kits are starting to show up online. Im sure we will see more performance parts for these motors as they become more popular.

[ChondaChondaChonda]

Got the head bolted on and the shop heater ran out of propane. So I'll be finishing it up tomorrow. Also hoping to run down to visit the Pitster dealer and see what a radiator and fan will cost me.

[JerryHawk250]

Nice upgrade and videos. That should give it that extra umph. Looks like fun but man those rocks look hard. lol That looks like a good bit of carbon build up on the piston but the head seems okay. It must be from all the low speed riding and putting under a load on the trail riding. How many miles or should I say hour you think you have on it?

[ChondaChondaChonda]

Originally Posted by JerryHawk250

Nice upgrade and videos. That should give it that extra umph. Looks like fun but man those rocks look hard. lol That looks like a good bit of carbon build up on the piston but the head seems okay. It must be from all the low speed riding and putting under a load on the trail riding. How many miles or should I say hour you think you have on it?

Our Tour of Idaho alone was 110 hours, so I'm estimating right around 200 hours total. Still ran excellent, I just wanted to try the big bore.

[JerryHawk250]

Looks like the design of the stock piston with the cut out areas for the valves at the edge allowed the carbon to collect and get imbedded in the cylinder wall which in turn started to scare the piston and cylinder wall. The new one looks like a much better design with the top of the piston being the same all the way around.

[ChondaChondaChonda]

[Megadan]

Originally Posted by JerryHawk250

Looks like the design of the stock piston with the cut out areas for the valves at the edge allowed the carbon to collect and get imbedded in the cylinder wall which in turn started to scare the piston and cylinder wall. The new one looks like a much better design with the top of the piston being the same all the way around.

That is possible, but something else I noticed was the wear marks on the edge of the crown right before the piston top. It almost looks like the cylinder wall clearance was a bit loose on the stock cylinder and piston. That rocking can also explain some of the skirt wear on the coating.

I would be interested to know if that old cylinder is out of round at all.

Also, every NC250/ZS177MM piston I have seen not only has the skirt coating, but also has a black thermal coating on the piston top. It is possible that there isn't as much carbon on the piston as you think. Example: https://www.aliexpress.com/item/Moto...825144309.html

If my math is right, that big ol' piston should put you right around 280ish CC's, which is a nice bump in displacement.

[Megadan]

I honestly wouldn't be surprised if the radiator guards for the same KTM XCW200 the fuel tank is for would possibly work on this bike as well. A little meauring tape work would easily answer that question. If so, then the frame style guards like the Moose Racing units would be a good option.

Every time I come back to this thread it makes me keep considering trading up my Hawk for one of these guys or an SSR SR450S. Stuff like the big bore kit doesn't help either! lol

[BlackBike]

Time for someone with a 2015 out of warr rx3 to step up and pop one on. 280cc would be help with winds and the grades

[Megadan]

What I would love to know is what they did to drop 6hp from the motor for the rx3. Same compression ratio, so it might be the cam profile, or something with the ports on the head casting. I would guess the camshaft, but no way of knowing.

[ChondaChondaChonda]

Originally Posted by Megadan

What I would love to know is what they did to drop 6hp from the motor for the rx3. Same compression ratio, so it might be the cam profile, or something with the ports on the head casting. I would guess the camshaft, but no way of knowing.

I don't think there is any difference in the motors physically. There are 2 things going on here.
1. The specs on the Pitster are known to be innacurate. The weigh and the gearing are verified to be incorrect.
2. Emissions compliance probably costs the RX3 a few ponies. My hunch is that the Pitster runs a much more fuel rich AFR across the tables and especially rich at high load/high throttle conditions. (Think accelerator pump rich) I can tell you that the bike runs on the rich side, you can actually smell it at times. No way that would pass muster on a certification test.

I bet if you were to dyno them side by side, then difference is less than 2hp.

[JagLite]

Doesn't the RX3 use a Delphi FI and the Pitster (Kayo) uses a different FI system?
The tuning could make a big difference.
Are both systems self-learning or just the Pitster?