New RK Tek User results thread

[rotax]

Kelsey,

For someone who wants your drop in kit and wants to go with the stock cheater head option.... Do you supply an complete new head with the domes or does a guy have to supply his head to get machined???
Also is there any performance difference between the cheater head and the billet head??

Thx,

Lindy

Also interested in both questions.
Can I return my stock head as a "core" after I drop-in? Thus, less down time?

I believe the Billet head may have better cooling characteristics (that can't be spelled right??)... Anyway, in which case could attribute to an engine heat soaking slower.
But, I'm also considering just a cheater as well to save some $, but I want the domes if I'm tearing down the top end, even if they are the same compression.

Crunching RKT's dyno numbers (yeah yeah, I know..) shows:
+1.6HP / +2TRQ gain @ 4200 RPM
2.14HP/2.3TRQ @ 5000
4.59HP/3.9TRQ @ 6000
4.1HP/3.1TRQ @ 7000
7.4HP/5.1TRQ @ 7500
7.9-8HP/5.2TRQ @ 7800-8000 [peak TRQ]
6.5HP/4TRQ @ 8200 [peak HP]

Those are solid gains for 6000+ (mid range to WOT), 12.5-1 compression stock VS 12.5-1 comp RKT.
I'm personally consider a 13.1-1 just to play it safe..
There may be a 1% chance that my sled would ever be used below 2-3000 feet anyway..

I've run RKT's heads before and know they perform, on top of that I had the feeling that the engine was more 'responsive'/'snappy'?

 

[tinkerjohnson]

drop in

so i am running the 13 pro with the drop in. i was running the slp pipe (with slp stage 4 map) also but my sled was not running like the others with this setup not pulling rpm only about 8000 with 60g weights, so i put the stock pipe on with the boondocker box and so far i have run it and it pulls 8500 no problem now i havent had it on the mtn yet just at low elevation 5500 ft, i will have it on the hill soon and post my results also i have added no fuel and have had no det as of yet

 

[Jkinzer]

Kelsey,

For someone who wants your drop in kit and wants to go with the stock cheater head option.... Do you supply an complete new head with the domes or does a guy have to supply his head to get machined???
Also is there any performance difference between the cheater head and the billet head??

Thx,

Lindy

send in your head and he machines it out to fit his domes, will def. have better/more effeicient cooling with the billet head

 

[ditch1000]

Thanks for the replies. I talked to Kelsey today and pulled the trigger on the drop in kit with orange billet head and 13:1 domes. Can't wait to get this baby in and running. He said he is back ordered for a week on pistons. No big deal; I gotta work over xmas anyway and I want to get some run time on the KMOD first. Gonna bolt that bad boy in tomorrow.

 

[snobyrd]

Thanks for the replies. I talked to Kelsey today and pulled the trigger on the drop in kit with orange billet head and 13:1 domes. Can't wait to get this baby in and running. He said he is back ordered for a week on pistons. No big deal; I gotta work over xmas anyway and I want to get some run time on the KMOD first. Gonna bolt that bad boy in tomorrow.

I'm waiting as well, did u buy a boonie box as well?

 

[ditch1000]

No I did not. He said on a 12 you do not need a box. If I needed one, I wouldn't have bought the kit. I had nothing but problems with them on my old M1000. The biggest thing I like about Kelseys kit other than the performance is that you run it without a controller. Can't wait to install it in a couple weeks. What compression ratio did you go with?? Keep me posted on your install.

 

[snobyrd]

No I did not. He said on a 12 you do not need a box. If I needed one, I wouldn't have bought the kit. I had nothing but problems with them on my old M1000. The biggest thing I like about Kelseys kit other than the performance is that you run it without a controller. Can't wait to install it in a couple weeks. What compression ratio did you go with?? Keep me posted on your install.

We will probably get our kits the same time lol
I'm going with 13.5, I don't want to run a box either but the 13s are leaner, and apparently it in the mid range that might need a bit of fuel

 

[tinkerjohnson]

We will probably get our kits the same time lol
I'm going with 13.5, I don't want to run a box either but the 13s are leaner, and apparently it in the mid range that might need a bit of fuel

i have a 13 with the drop in kit running the 14-1 head at 5500 ft no added fuel and no det problems not sure your alt but i ride at 10000 most the time just tuning at the house and i have added no fuel with my boondocker box as of yet it may just be at higher alt the sled leans out a little too much in the mid i will find out tomorrow.

 

[snobyrd]

i have a 13 with the drop in kit running the 14-1 head at 5500 ft no added fuel and no det problems not sure your alt but i ride at 10000 most the time just tuning at the house and i have added no fuel with my boondocker box as of yet it may just be at higher alt the sled leans out a little too much in the mid i will find out tomorrow.

I'm at 3-5000',I was worried a bit with goin with a 13.5 head, I was even planing on addin a touch of race or av gas, good to hear.
What are u usin for a clutch setup, I've got 68 grm pol weights sitting here and that's it.
What's your track speed when your digging hard, mine in stock forum is 41-42, hope that number goes up with the kit...

 

[tinkerjohnson]

I'm at 3-5000',I was worried a bit with goin with a 13.5 head, I was even planing on addin a touch of race or av gas, good to hear.
What are u usin for a clutch setup, I've got 68 grm pol weights sitting here and that's it.
What's your track speed when your digging hard, mine in stock forum is 41-42, hope that number goes up with the kit...

i would say probabbly 64g maybe 66g weights for that elevation you want this engine to run 8300 8400 rpm with this setup and it may even like to be loaded even heavier with weight you may find it will pull harder down in the 8100 8200 area i havent figured that part out yet, not had enough tuning done at elevation with this setup i ride at 8000 to 10000 elevation, i was only riding the fields in town here at 5500 really wasnt even looking at track speed im only riding the flats so no info on that, but engine revs so fast i hit 8500 at the blip of the throttle but i am clutched for higher elevation also. but i think guys in the lower elevation may be ok without the control box no sign of det with high comp head down low on mine but only riding your conditions and setup will be the true test for you

 

[snobyrd]

i would say probabbly 64g maybe 66g weights for that elevation you want this engine to run 8300 8400 rpm with this setup and it may even like to be loaded even heavier with weight you may find it will pull harder down in the 8100 8200 area i havent figured that part out yet, not had enough tuning done at elevation with this setup i ride at 8000 to 10000 elevation, i was only riding the fields in town here at 5500 really wasnt even looking at track speed im only riding the flats so no info on that, but engine revs so fast i hit 8500 at the blip of the throttle but i am clutched for higher elevation also. but i think guys in the lower elevation may be ok without the control box no sign of det with high comp head down low on mine but only riding your conditions and setup will be the true test for you

I'm running 64 now, and I'm hitting 8450 on the road ride in at 3500' so I'm guessing 68 if this kit makes the kind of power claimed. Did u change the helix or springs?

 

[tinkerjohnson]

I'm running 64 now, and I'm hitting 8450 on the road ride in at 3500' so I'm guessing 68 if this kit makes the kind of power claimed. Did u change the helix or springs?

i am running the tied driven, but i would try the stock clutching in the rear and i would try your 68g weghts and use that as a baseline and adjust from there

 

[Trxstr]

I just installed the drop in factory replacement pistons in my '12 rmk 800. Factory ones looked fine but wanted to tighten things up. I do have a question for anyone who can answer... When I put the rod bearing in and the piston on, then insert the pin, it seems like there is a lot of side to side play from the piston on the wrist pin. Will this cause the bearing to slide out each side a little even when the pistons are in the cylinders??? Thanks...

 

[mtncat1]

no that's the way they are designed they are fine like that,rode with my kit today working much better with 10-60s taching a 8300 on flats,8100 on hills using non eth plug,pulling much harder in the mid range and seems to be getting better every ride,comparing to my freinds stock 11 pro.only problem i had was det code twice and went into detune once.gonna try with ethanol plug next thanks for your help kelsey

 

[tinkerjohnson]

13 drop in update

so i went out riding my 13 with drop in kit and stock pipe, it looks like a fuel controller is a must on the 13 i had det for sure i tried it with no added fuel and not ganna work, i was detting continuiously in the mid and top. i have the fuel controller so i added fuel about 5% throughout the midrange and 10% on the top end runs strong and no det, i am running a innovate afr to help with the tuning. i got it setup running strong pulls hard and runns smooth i was hoping it would be ok without but it needs more fuel. i am running non eth 91 fuel in the non eth setting and riding between 7 and 11000ft using a boondocker box, i have the numbers i am running i will give you guys to try if needed for a baseline you can adjust from there if needed. i put 70 miles on today with no problems after i got the fuel numbers set. sled is tacking from 8100 to 8300

 

[rotax]

no that's the way they are designed they are fine like that,rode with my kit today working much better with 10-60s taching a 8300 on flats,8100 on hills using non eth plug,pulling much harder in the mid range and seems to be getting better every ride,comparing to my freinds stock 11 pro.only problem i had was det code twice and went into detune once.gonna try with ethanol plug next thanks for your help kelsey

what compression head and elevation?

this is exactly why i want to run a much lower compression than required for elevation dome if I go this route...
det is always a pita, I don't want anything to do with it, ever.

Hope you can make up for the det issue w/ the ethanol resistor.

 

[snobyrd]

what compression head and elevation?

this is exactly why i want to run a much lower compression than required for elevation dome if I go this route...
det is always a pita, I don't want anything to do with it, ever.

Hope you can make up for the det issue w/ the ethanol resistor.

my conversation with Kelsey was about this det issue, he said it's leaning out in the mid at high ele, it's not detonation, so from wat I gather, u could run race fuel and still get the det code, it needs more fuel, so I don't think head ratio is the problem, Kelsey said it will give a det code if it's lean as well. Correct me if I'm wrong.

 

[snobyrd]

so i went out riding my 13 with drop in kit and stock pipe, it looks like a fuel controller is a must on the 13 i had det for sure i tried it with no added fuel and not ganna work, i was detting continuiously in the mid and top. i have the fuel controller so i added fuel about 5% throughout the midrange and 10% on the top end runs strong and no det, i am running a innovate afr to help with the tuning. i got it setup running strong pulls hard and runns smooth i was hoping it would be ok without but it needs more fuel. i am running non eth 91 fuel in the non eth setting and riding between 7 and 11000ft using a boondocker box, i have the numbers i am running i will give you guys to try if needed for a baseline you can adjust from there if needed. i put 70 miles on today with no problems after i got the fuel numbers set. sled is tacking from 8100 to 8300

Could u please post your boonie.box numbers, also wats your innovate afr? A brand or your own rigging?
Tks

 

[dirtymax]

det issues is a pita with this kit im running 2011 with drop in kit and head ethonal chip in and running 91 ethonal with 1 gallon of race and stiil throws a det code once in a while riding 7000 to 9000 ft yesterday going up ran fine up high ran like a top comming down last nite thru the code 5 times explain that this is frustrating the h--l out of me

 

[PaulAnd]

April snow 2012 Cooke city 7-10k
2010 cfi-4 800 Assault 146
Rktek kit with head (black), stock compression domes (for now)
stock clutching and stock fresh springs, stock helix
stock exhaust
no fuel controller
stock competition track
ehtanol wires unplugged
ves hoses plugged with wrong springs (bog from stop) replaced hose (no bog now)
I had in the 10-60's (wasnt sure, thats why i'm reposting)
was running max rpm 8450
didnt check track speed, sorry
2013 season made some changes... 153" 2.5" C.E. Avid 7tooth 3" drivers, 2:14 gear ratio c3 belt drive, carls helix, trying stock secondary spring, Starting with 10-64's(heaviest I have) @ 1k to 2k elevation, have not tried it yet...