RK TeK 860 Big Bore Kit

RKT · Jan 7, 2012

It would be just CRAZY TALK to listen to the manufacturer/designer of the kit (who puts 3,000 miles on the kit ever year) and set it up per those instructions...

That would just be NUTS!!

That 860 will run like a bucket of ***** with 500 mains!! Stockers will run circles around it set up like that..

Really.. What is so hard about setting it up correctly.. (100% , not partial..correct)??? You have all the details.. Just follow them and enjoy the kit.. Second guessing the instructions will only ruin your season with a poor running sled.

Backcountrypro · Jan 7, 2012

Kelsey has never steered me wrong on jetting. His recommendations are dead on. Throw the 460's in, shim the needles, vary the throttle on the trail and enjoy the kit!

Trickle860 · Jan 8, 2012

Right right right. We will take the 500's out. Now if only the damn ecm works...

stonehands1 · Jan 8, 2012

RKT said:
It would be just CRAZY TALK to listen to the manufacturer/designer of the kit (who puts 3,000 miles on the kit ever year) and set it up per those instructions...

That would just be NUTS!!

That 860 will run like a bucket of ***** with 500 mains!! Stockers will run circles around it set up like that..

Really.. What is so hard about setting it up correctly.. (100% , not partial..correct)??? You have all the details.. Just follow them and enjoy the kit.. Second guessing the instructions will only ruin your season with a poor running sled.

Kelsey I do respect you and your work... but your statement highlighted in red just makes you sound stupid. Whenever you would like to bring your stocker out to the coast and run circles around my 860 with 500 mains I'd be more than happy to hand you your stock azz anytime.
In fact let me just say that my buddy bought your drop in kit,head,y pipe, ecm reflash and clutching and I took my other buddies show room floor stock 800 and wax your kit hands down every race.
I would normally not bash but your statement is so bullshat it deserved a reply.

stonehands1 · Jan 8, 2012

EDIT: I just realized that you could be talking about your 860 with 500 mains getting waxed by a stocker.
If that's is the case then I agree with you completely.

winter brew · Jan 8, 2012

Setup you sled exactly as RKT, john or whoever you are dealing with down to the last detail.... Jetting, reeds, exhaust etc... Remember they WANT your sled to run strong and reliably, their success depends on it.
Then if you have any issues you wont be going back and making changes, it makes it easier for everyone involved.
One piece of advice on any BB....run good fuel! The quality (octane) is as important as the quantity.

pfi572 · Jan 8, 2012

These engines run great when set up correct. The most inportant thing is fuel and what elevation you are running at.
When i ordered my kit we talked about elevation and i ride from 3500ft up 6500 ft mostly and some 8000 but not that much.
The recommended was 14:1 with the 460 mains and 2007 needles. I have allready stated this in thread above.
I couldn't not run that low of jetting . Have had others in this area that run the same BB with14:1 and lower jetting and didn't work out either.
I think that 13:1 with #1 fuel would have worked with the lower jetting.
On mine as soon as i started running 20 to 30% 110 and raised the jetting sled ran very strong and no troubles.
I liked my 860 and would still be running it if i hadn't bought another sled with something else allready installed.
Would i buy another RKT you bet but would drop to 13:1 for the elevation i ride. This is what i have in the one i ride at this time and havent had one problem.
Kelsey,Big John and other builders thanks for all the work you all put into this but i think the fuel quality is what kills these motors.
To be on the safe side drop comp. or run the better fuel. IMO

RKT · Jan 8, 2012

Fuel quality has certainly taken a turn for the worse in the last 3 years... 14:1 at your elevation (here in the states) 2-3 years ago was fine.. Now, it needs to be lessened, in fact we have changed the head design completely to adjust for the bad fuel..

I DO run 14.8:1 on pump gas from 6k to 9500ft.. and have done since 1995.. Only last year did the fuel get so bad that I had to mix 25% Av Gas 100LL to avoid issues on the SAME sled that I have been running for 4 years. So, YES, the fuel quality has changed..

Really too bad... but we have made adjustments to compensate... hence the jetting requirements are accurate for the current fuel on all new builds.

PFI your build was 2008.. The fuel was better then, the head was different, and the 860 kit was very different than it is today..
Design changes every year, what was relevant in 2008, 2009, and 2010 builds is not AS relevant with 2011 and 2012 builds.. We adjust and,hopefully, make improvements..

Again.. the engine kit and head designs go through MANY alterations and configurations EVERY SEASON. We changed the 860 3 times last season and made some very serious performance gains.. Enough, that I am probably finished altering it..

But, good and valid point on the fuel quality.. It is a major concern these days. But we have taken many steps to address it and the current "set up" instructions are correct for today's fuel and kit's design

Kelsey

Trickle860 · Jan 24, 2012

Update from ground zero

Kelsey,
So I have 54 miles on the new set up. I have been running about %35 110 fuel and only non ethanol 91. (433 ramps and 17.16 gram weights. Purple purple on both stock and secondary and still 500 jets) My elevation has been starting at 3800 ft and ending just under 7000 ft. All I do is vary the throttle constantly trying to not stay within the 6000-7000 rpm for too long. At first as expected the thing ran a little doggish. Yesterday in 3ft of bottomless fresh blower power the thing came alive. I finally let loose the thunder and out climbed my friends etec (which only has 150 miles on it.) I am surrounded by opponents on all sides regarding the jetting. Tomorrow morning we are going to step it down from 500 back to the original 480's and check the plugs after hard pulls to see the results. Here is my question; my rpms so far will not hold on 8300 rpms on the stock summit x digital gauge. They hit 8300 here and there but more often I see 8000 or 8100. My clickers are already up to 4 (which seems too high for the new clutching setup). I'm wondering if I should change weights or see what dropping the jetting does for me.

Second question which is unrelated to your engine performance but a serious issue. When at low rpms (below 2000) my battery light comes on, then when I gas it the light comes off until around 6000 rpms where every now and then the light comes back on and my headlights dim. Could this be related to the potentially bad ECM like Tom thought or do you think I have a short or a bad stater?

p.s. I am so happy the thing hasn't blown yet and plan on jetting down while monitoring the plugs. I have taken the utmost care in breaking it in correctly. I'm confident I will be kicking everyone's asses in the area soon enough.

RKT said:
Fuel quality has certainly taken a turn for the worse in the last 3 years... 14:1 at your elevation (here in the states) 2-3 years ago was fine.. Now, it needs to be lessened, in fact we have changed the head design completely to adjust for the bad fuel..

I DO run 14.8:1 on pump gas from 6k to 9500ft.. and have done since 1995.. Only last year did the fuel get so bad that I had to mix 25% Av Gas 100LL to avoid issues on the SAME sled that I have been running for 4 years. So, YES, the fuel quality has changed..

Really too bad... but we have made adjustments to compensate... hence the jetting requirements are accurate for the current fuel on all new builds.

PFI your build was 2008.. The fuel was better then, the head was different, and the 860 kit was very different than it is today..
Design changes every year, what was relevant in 2008, 2009, and 2010 builds is not AS relevant with 2011 and 2012 builds.. We adjust and,hopefully, make improvements..

Again.. the engine kit and head designs go through MANY alterations and configurations EVERY SEASON. We changed the 860 3 times last season and made some very serious performance gains.. Enough, that I am probably finished altering it..

But, good and valid point on the fuel quality.. It is a major concern these days. But we have taken many steps to address it and the current "set up" instructions are correct for today's fuel and kit's design

Kelsey

RKT · Jan 25, 2012

Trickle860 said:
Kelsey,
So I have 54 miles on the new set up. I have been running about %35 110 fuel and only non ethanol 91. (433 ramps and 17.16 gram weights. Purple purple on both stock and secondary and still 500 jets) My elevation has been starting at 3800 ft and ending just under 7000 ft. All I do is vary the throttle constantly trying to not stay within the 6000-7000 rpm for too long. At first as expected the thing ran a little doggish. Yesterday in 3ft of bottomless fresh blower power the thing came alive. I finally let loose the thunder and out climbed my friends etec (which only has 150 miles on it.) I am surrounded by opponents on all sides regarding the jetting. Tomorrow morning we are going to step it down from 500 back to the original 480's and check the plugs after hard pulls to see the results. Here is my question; my rpms so far will not hold on 8300 rpms on the stock summit x digital gauge. They hit 8300 here and there but more often I see 8000 or 8100. My clickers are already up to 4 (which seems too high for the new clutching setup). I'm wondering if I should change weights or see what dropping the jetting does for me.

Second question which is unrelated to your engine performance but a serious issue. When at low rpms (below 2000) my battery light comes on, then when I gas it the light comes off until around 6000 rpms where every now and then the light comes back on and my headlights dim. Could this be related to the potentially bad ECM like Tom thought or do you think I have a short or a bad stater?

p.s. I am so happy the thing hasn't blown yet and plan on jetting down while monitoring the plugs. I have taken the utmost care in breaking it in correctly. I'm confident I will be kicking everyone's asses in the area soon enough.

The engine will never hold rpms when it is drowning in fuel nor will it make good power.. With a 500 main jet, it is drowning.. drop to a 460 and then clicker down to 1 or 2 and you will see what she is made of.. Since your ECM was flagged.. you MAY not even have the correct reprogramming installed and if this is the case, 8100-8200 will be your optimum rpms . So, see where it feels the best..

Another note: your crank is brand new.. it will not fully loosen up till about 400 miles or so.. power will increase when this happens .

The head light dimming and such, I would not think is ecm related I would suspect a bad stator or regulator.. or maybe even a loose wire.

OH,,, reading plugs when using any leaded fuel (like you are doing) is useless.. They will be pure porcelin white when they are right. So, might as well never pull them and just jet down to start..

One other thing,, using 35% 110 like you mentioned.. I suspect 420-430 main jets would be more in the ballpark. PLEASE do what I suggest and just use 30% (100 LL NOT 110) , install 460's clicker down and run it .. you are barely at stock power levels with your current set up.. The kit has been around for 5 years.. there are no mysteries in this area..

sonic · Jan 25, 2012

RKT said:
The engine will never hold rpms when it is drowning in fuel nor will it make good power.. With a 500 main jet, it is drowning.. drop to a 460 and then clicker down to 1 or 2 and you will see what she is made of.. Since your ECM was flagged.. you MAY not even have the correct reprogramming installed and if this is the case, 8100-8200 will be your optimum rpms . So, see where it feels the best..

Another note: your crank is brand new.. it will not fully loosen up till about 400 miles or so.. power will increase when this happens .

The head light dimming and such, I would not think is ecm related I would suspect a bad stator or regulator.. or maybe even a loose wire.

OH,,, reading plugs when using any leaded fuel (like you are doing) is useless.. They will be pure porcelin white when they are right. So, might as well never pull them and just jet down to start..

One other thing,, using 35% 110 like you mentioned.. I suspect 420-430 main jets would be more in the ballpark. PLEASE do what I suggest and just use 30% (100 LL NOT 110) , install 460's clicker down and run it .. you are barely at stock power levels with your current set up.. The kit has been around for 5 years.. there are no mysteries in this area..

i run 433 ramps straight pump gas pl/pl primary team secondary 460 mains clicker 1 20 grams of weight i can keep the rpm hand in the green 07 rev thanks kelsey

mtnjunkie · Jan 25, 2012

I'm running Kelseys 860 and did what he suggested with 460 mains, 07 needles, stock pilots. It actually is a little rich, we ride from 5000 to 10000 ft. And I do mix about 30% 100ll. I might need to jet down a bit, just haven't yet as we were just able to start riding this week.

Kelsey's been building these for a while, he doesn't want you to burn your sled down. If he suggests 460s for your sled then I would trust him. Trusting opinions from people who have never ran his motor, or any bb, over the builder's instructions doesn't really make sense. He's not just throwing parts together and sending them to you, he tests them and rides them harder than most people will. He knows how to make them run.

I wonder how many people who've burned up their motor up followed all recommendations? I mean, how many put on a different pipe, used bad fuel, rode drastically different elevations than it was built for, etc. That wouldn't really be the fault of the the motor or the builder.

Right about the lead changing colors, will make plugs anywhere from light brown to white depending on the jetting, I've seen a little yellow on mine too. Pistons are a burnt orange color. Checking plugs is pretty useless with avgas.

doo-rev · Jan 28, 2012

My 860 with Kelsey's setup is pulling 23.5 Grams in the Primary. Kelsey says that it is not shifting out like it should. Anyone have any ideas to why it is not shifting out? Can it be binding somehow. Any ideas would be appreciated.

portgrinder · Jan 28, 2012

DITCHBANGER said:
If your oil cable breaks it goes full rich... No disaster

sorry to sidetrack here but fthe rayed cables when they break frequently cause the throttle to stick as well. and we all know throttles only stick wide open. can be serious health issues if not wearing yer teather.

stonehands1 · Jan 29, 2012

doo-rev said:
My 860 with Kelsey's setup is pulling 23.5 Grams in the Primary. Kelsey says that it is not shifting out like it should. Anyone have any ideas to why it is not shifting out? Can it be binding somehow. Any ideas would be appreciated.

Are your clutches in good order? All rebuilt and moving freely? What springs and ramps are you running?

doo-rev · Jan 30, 2012

Everything seems to be moving freely in the clutches. Only 1000 miles on sled. Running a 160/320 primary and stock secondary

pfi572 · Jan 30, 2012

How do you know its not shifting out?
Not happy with performance?
Is the sled pulling hard and holding RPM?
What track length,helix ,spring,gearing,rider weight and elevation?
If i missed a post on this sorry but didn't see anything .:face-icon-small-con

doo-rev said:
My 860 with Kelsey's setup is pulling 23.5 Grams in the Primary. Kelsey says that it is not shifting out like it should. Anyone have any ideas to why it is not shifting out? Can it be binding somehow. Any ideas would be appreciated.

Backcountrypro · Jan 30, 2012

Here is video from Cooke this weekend. Temps were somewhat colder and guess what...the colder it got the better the engine ran. Running 460's and 2.5 gallons of av gas per tank.

Listen around the 2:20 mark.....engine sounds like it has a turbo on it!

http://www.youtube.com/watch?v=-l79TZJZKYA&list=UUtSneQpt0WM5daFRlXESquw&index=1&feature=plcp

RKT · Jan 30, 2012

Backcountrypro said:
Here is video from Cooke this weekend. Temps were somewhat colder and guess what...the colder it got the better the engine ran. Running 460's and 2.5 gallons of av gas per tank.

Listen around the 2:20 mark.....engine sounds like it has a turbo on it!

http://www.youtube.com/watch?v=-l79TZJZKYA&list=UUtSneQpt0WM5daFRlXESquw&index=1&feature=plcp

Good stuff..

Sounds like the engine is running well.. I think you are still a bit rich on the main jet.. But, leave it where it is at because it is still getting the job done..

Love to see vids of a sled that is going faster as it ascends hills vs. slower (like stockers and ??:face-icon-small-coo)

If I remember correctly, you struggled with the 860 for a whole season because you had "other" "Super" set ups installed than were recommended in my set-up sheet.. Once you set it up to the supplied recs.. it has been "ON" ever since..

I rode mine for the 1st time this year since last season and absolutely fell in love with it again,, Been riding the new Pro and Pro-Climb all season.. Need to get that 860 power in these new sleds.. .. working on that for next weekend on at least one of them..

Thanks for sharing

Kelsey

Backcountrypro · Jan 30, 2012

Yeah she is "ON" now! Everything is set to specs and I couldn't be happier.

This weekend in Cooke I bumped into a group of AC riders on new turbo'ed M8's-they pulled some incredible vertical lines up through the trees. I thought- "aw what the heck" lets see what the 860 can do. I picked my line next to theirs, pinned the throttle and happily watched my tach settle on 8200. I crested the top...skis packed in the air! Best part was on my return to the bottom of the hill I got a "thumbs up" from the turbo AC crowd! I think that speaks volumes for this engine.

Well done Kelsey!

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