RK TEK drop in piston kit for mxz 800r 2009

[Modman]

Another thing he told me was to jet DOWN and lean it out. I did WOT runs on a lake and did a plug check and they are a very light brown, kelsey said "that just tells you what color your oil burns" he basicly said checking your plug color is old school and that it does'nt mean anything. After that i am now a little worried about my purchase.

WTF?? So how do you know when you are too lean? After you scrape the piston off the side of the cylinder?

I check my plugs all the time, I run two little mods, both premixers and my plugs change colour all the time, even between sleds and in the past, both have run on the same oil, not on the same oil right now though but plugs still same colour as on the old oil.

 

[sledhead800]

WTF?? So how do you know when you are too lean? After you scrape the piston off the side of the cylinder?

I check my plugs all the time, I run two little mods, both premixers and my plugs change colour all the time, even between sleds and in the past, both have run on the same oil, not on the same oil right now though but plugs still same colour as on the old oil.

You got to check the piston for to see how much wash is on the piston that gives you the right reading on how much u can jet down.

 

[Modman]

You got to check the piston for to see how much wash is on the piston that gives you the right reading on how much u can jet down.

piston wash takes hours to develop, are you willing to ride around for a day before you can figure out if you are too lean? LOL

I'll keep checking my plugs.

 

[maxwell]

especially on a new motor you could be riding for days before there is enough wash to read

 

[thump]

WTF?? So how do you know when you are too lean? After you scrape the piston off the side of the cylinder?

I check my plugs all the time, I run two little mods, both premixers and my plugs change colour all the time, even between sleds and in the past, both have run on the same oil, not on the same oil right now though but plugs still same colour as on the old oil.

In 1995 I gave up on reading plugs after about 5 pistons and some cylinders in various machines. Since then I use a Race Pack EGT gauge on my sleds, No more melted pistons,,,,hmmmmm,,go figure:d. Price of meltdowns and downtime,,, way too much,,, Price of Race Pack $500,, I finally did the Math What I am saying is that if you want to run on the edge,,,then invest in a good Gauge and the guessing is gone. I dont run on the edge, but I do like to know how the engine is running and the gauge is a great tuning tool.

 

[maxwell]

how can you tell if your machine is working from an egt. that doesnt make sence. some machines i setup run 1100 and thats the max on the edge, some like 1300

depends on the exhaust, probe placement and 100 other variables.

you need to tune your machine ( plugs and wash ) then look at the egt.

 

[Slamnek]

I have around 200km on my motor, is that enough time to get a good wash reading?

 

[Modman]

In 1995 I gave up on reading plugs after about 5 pistons and some cylinders in various machines. Since then I use a Race Pack EGT gauge on my sleds, No more melted pistons,,,,hmmmmm,,go figure:d. Price of meltdowns and downtime,,, way too much,,, Price of Race Pack $500,, I finally did the Math What I am saying is that if you want to run on the edge,,,then invest in a good Gauge and the guessing is gone. I dont run on the edge, but I do like to know how the engine is running and the gauge is a great tuning tool.

I totally agree with getting a good gauge, but I don't rely on anything one item exclusively to tell me how my motor is running. I use a combination of EGTs, plugs, wash, rider feel, a/f gauge, etc and use many factors to confirm what I feel and see. Until you correlate the gauge to actual motor temps via the plug colours and piston wash after a few days of riding, the EGT readings mean nothing IMO, since EGT readings are variable depending on probe placement, pipe design, how hot the motor likes to run, etc. Some motors run really well at 1150, others don't start making power until 1200.

I run the KOSO EGTs on both my sleds and also now the KOSO A/F gauge. Even if you are not running on the edge, sleds burn down so often for other factors (air leaks, bad fuel, etc etc) that I recommend EGTs to anyone, simply from the standpoint that they can alert you that "something" is wrong when your motor changes how its running. Usually by the time you realize you are running too lean, its too late. With an EGT or A/F gauge as well, you might be able to identify that "something" is wrong before it causes catastrophic damage.

Most people think that EGT and A/F gauges are just for the guys that are running on the edge, but as you stated, its nice to know whats actually going on in your motor for peace of mind as well. A few $$$ up front can save a big repair bill down the road.

 

[thump]

I totally agree with getting a good gauge, but I don't rely on anything one item exclusively to tell me how my motor is running. I use a combination of EGTs, plugs, wash, rider feel, a/f gauge, etc and use many factors to confirm what I feel and see. Until you correlate the gauge to actual motor temps via the plug colours and piston wash after a few days of riding, the EGT readings mean nothing IMO, since EGT readings are variable depending on probe placement, pipe design, how hot the motor likes to run, etc. Some motors run really well at 1150, others don't start making power until 1200.

I run the KOSO EGTs on both my sleds and also now the KOSO A/F gauge. Even if you are not running on the edge, sleds burn down so often for other factors (air leaks, bad fuel, etc etc) that I recommend EGTs to anyone, simply from the standpoint that they can alert you that "something" is wrong when your motor changes how its running. Usually by the time you realize you are running too lean, its too late. With an EGT or A/F gauge as well, you might be able to identify that "something" is wrong before it causes catastrophic damage.

Most people think that EGT and A/F gauges are just for the guys that are running on the edge, but as you stated, its nice to know whats actually going on in your motor for peace of mind as well. A few $$$ up front can save a big repair bill down the road.

I do agree with you,,, just sayin that since I started to use an EGT gauge I was able to put more $$$ towards more mountain trips:d rather than pullin wrenches Works for me.

 

[Modman]

I have around 200km on my motor, is that enough time to get a good wash reading?

If you can see wash on your pistons then yes, usually it takes a while to develop, 200 kms....its probably starting to show. Easiest thing to do is split pipe at Y pipe junction, pull plugs and stick a long flexible flashlight up the Y pipe into the cylinder and then look through the plug hole to see what the wash looks like.

 

[Slamnek]

What should a good wash look like? I remember reading something like it should be half the diameter of a dime around the piston crown. Please correct me if i'm wrong

 

[Slamnek]

I just found this picture.

 

[Modman]

Middle one in your photo still seems slightly rich to me.

IMO - they should look more like the first one pictured here:



Just a little bit of wash around the transfers and slightly around the edge of the whole dome. I think anywhere in between your's and this one and you should be good. I wouldn't go leaner than this and I wouldn't go richer than the middle one in your photo.

 

[Caper11]

how can you tell if your machine is working from an egt. that doesnt make sence. some machines i setup run 1100 and thats the max on the edge, some like 1300

depends on the exhaust, probe placement and 100 other variables.

you need to tune your machine ( plugs and wash ) then look at the egt.

Well said!!, in the end a EGT guage is still a electronic device, and IF it's installed correctly and maintained correctly, it works good. but i've been called out to site so many times about a cold hole on a engine, and it turns out to be a bad thremocouple or flaky wire.
Best advice is learn to read the piston wash.

 

[grahamkomada]

Kelsey knows what he is talking about. I have the 827 and my 04 summit runs with 1000cc cats and new xps. If you listen to what he says your machine will fly. Pipes can yield little or no gain, which is why he does not recommend. However intake mods, like an 07 intake box or bondi air box, (i run an timbersled intake with a full 5 pc vent kit) will help over all power. The mpem re curve is a timing thing, it will help with fuel economy(cuz the engine isn't using more fuel in the mid range than it needs) as well as mid range power. It makes your engine run more efficient.

He does however recommend strongly that you run the stock can( or a skinz super Q or ultra Q) this is a must. aftermarket cans are to restrictive and will destroy your engine.

If you follow his advice you will see noticeable gains. And if all else fails Call him. He provides customer service that is second to none.

 

[Slamnek]

Kelsey knows what he is talking about. I have the 827 and my 04 summit runs with 1000cc cats and new xps. If you listen to what he says your machine will fly. Pipes can yield little or no gain, which is why he does not recommend. However intake mods, like an 07 intake box or bondi air box, (i run an timbersled intake with a full 5 pc vent kit) will help over all power. The mpem re curve is a timing thing, it will help with fuel economy(cuz the engine isn't using more fuel in the mid range than it needs) as well as mid range power. It makes your engine run more efficient.

He does however recommend strongly that you run the stock can( or a skinz super Q or ultra Q) this is a must. aftermarket cans are to restrictive and will destroy your engine.

If you follow his advice you will see noticeable gains. And if all else fails Call him. He provides customer service that is second to none.

Thanks for the input. I'm pretty sure that aftermarket cans are less restrictive than stock. Did you have to do any other tuning with the timbersled intake as i am looking at getting one for my 05?

 

[grahamkomada]

After market cans are more restrictive than stock. Thats why some produce a small hp gain, as they create a slight back pressure. But you could create the same small hp gain by jetting down 1 size.

Do you really think ski doo or any manufacturer for that matter would release sleds to the public that are tuned to create max hp. No! They release sleds that create reasonable power, but are reliable, and idiot proof. They jet rich, have pipes and cans that are less restrictive but safer. 98% of people want a sled they can pull and go. And they have no idea how to maintain or tune, they just want to hold the throttle wide open all day. Can you imagine the warranty claims if manufacturers release race tuned sleds to the public that had no idea how to take care of them.

Kelsey knows his stuff, if you do some reseach on 2strokeheads.com you will see that. Do what he recommends and you sleds will pull your arms off.

I did timbersled intake and vforce reeds, stock pipe and an Ultra Q can. As the Skinz super and ultra q are the only cans that kelsey has tested and deemed big bore safe. I also did a 5 pc modrods vent kit to keep the intake getting lots of cold air.

 

[Slamnek]

Thanks man. I know i need to do some clutching adjustments on the primary, probably going to do the DJ kit and try the stock pipe. As it sits, my sled pulls awesome down here but i haven't had a chance to ride it in the hills since i had my clutchs cleaned and a new spring in my team secondary.

 

[grahamkomada]

the only thing i did to the clutch was a 160/320 spring in primary and dalton midweight adjustable weights and she pulls like a mother...... Can is the biggest thing that could cause problems. You have to think all of these cans are deigned to bolt on and make a couple hp on a stock motor. lets say a generous 135 in the 800 ho. Now add 25-40 HP on top of that. those restrictive cans that made a little hp and sounded great on a stock motor, not create far to much back pressure for the power your engine now puts out.You may be able to run a can with the drop in piston kit i dont know, when in doubt i call kelsey. And since i've started to listen my sled hauls ass. Just my .02.....

 

[Slamnek]

Ya Kelsey told me to run a stock pipe and can for the best performance. I may have to try that ultra Q with a stock pipe. I don't think i could ever run the stock muffler, my crankshop single and MBRP sounds really good and even better since i got the drop in kit.