800R big bore kits....whose do you have, and how's it workin?

[teeroy]

Alrighty then, what big bore kit are you running in your XP? Found out today after cleaning up the smear of aluminum that my jug is toast....not badly scratched, but found pits in the coating. Thinking of going big bore and would like to read any thoughts or experiences that you have with any of the aftermarket kits. The good, the bad, and the ugly.....let's have it.

 

[DaveB]

PM sent.

 

[jaredszakacs]

had a split second 860 w/twins and nos in my 08 and worked real well I recommend MOTTS,SPLIT SECOND,AND ARCTIC EDGE all three make real nice power and a good reliable BigBore

 

[turbostang]

dave french at a@e racing built mine, jaws twins, thing flat out rips...

 

[rotaxtothemax]

880 twin pipes splitsecond ralph 780 524 4330 good engines

 

[oler1234]

had a split second 860 w/twins and nos in my 08 and worked real well I recommend MOTTS,SPLIT SECOND,AND ARCTIC EDGE all three make real nice power and a good reliable BigBore

i will second the arctic edge setup with twins and nos, works awasome and no problems yet.

 

[ryan#1]

860 by Specialty/RK Tek. Not a lot of km on it yet but it is pretty impressive so far. Hasn't missed a beat. Pulls about 10mph more track speed than my stock 146 and gets there a lot faster too. The only negative I would say so far is the VP mix is a bit expensive. It is better on fuel than I thought too...it burns about the same as my stock sled 100-110km of hard riding per tank. It has NOS too but I haven't used it yet...scared i will blow it up and it is an expensive motor.

 

[fredw]

880 twin pipes splitsecond ralph 780 524 4330 good engines

 

[TABSTER]

who has installed there own? and dialed it in? maybe some set up tidbits might be useful.

 

[teeroy]

who has installed there own? and dialed it in? maybe some set up tidbits might be useful.

good call tabs....yes I will be doing the install and tuning myself, and appreciate the input.

 

[DaveB]

FYI: twins work real well on stock 800r motors....so some of these big bores with twins...well...how much extra power is from the BB, and how much is from the twin pipes?

 

[fredw]

i installed mine

if your doing just the topend, its a basic job

take head off, take jugs off, take pistons off of rods and send head and jugs away, 2 hrs max

i did the 880 package from splitsecond, and ended up with over 20 grams in the stock primary with a spring preload of 130/230

my stock 800 previously came with around 12 grams and a 160/320.... to give you a indication of power

bj, ralph, mots, do great work

 

[maxwell]

if you can install a big bore in 2 hours i will cook you a gigantic cookie.

 

[maxwell]

you both know my position SO FAR.

this year i am running an SHR 860 and BMP 880.

these kits are both pump gas so automatically i am not receiveing the MAX amount of hp available.

for the 880...

500 mains RICH 20 thou needle shim,no reflash,, STOCK clutching,stock exhaust and specialty can 174x2.5. and this is where my problem lies as the owner has not yet allowed me to installed the correct clutching and this sled cant be fairly compared without the correct clutching.

what i have noticed about this engine is the torque. last season it was having an issue pulling the stock 154 track on clicker 5. after the installation of the big bore and the 174 track it now pulls it no problems on clicker 2. this tells me that it is making more power to acheive this. however these motors like load and we are not creating this with the factory clutching and pin weight.

this has been a pull and go real good runner. i would imagine keeping the stock length track and the correct clutching you would notice a good power increase. we plan to get cory miku to send us a clucth setup in the near future. once i have this engine dialed in i will be sure to give an honest report. right now there is alot of room for me to move on the jetting and clutching. but with that said i wouldbe interested in how it compares with a 174 witha STOCK engine. i do not have any of these. i should also tell you that i am running 19/45 gearing which is what most are running with there stock 154/146 tracks and this engine pulls the 174 with that gearing all day long at 8100rpm.



the 860...

same sled. 174x2.5 with 19/45 gearing, 20 thou needle shim, 470 mains. SHR 860. clutching is roosterbuilt 860 specific clutching.no reflash. SLP ypipe and slp can. stock pipe. JOHN says not to run the slp can it was the only can to lose HP when the engine was dynoed. the slp y pipe is ok as anything is better than the stock one. i have an HPS can i am going to try on this 860 on the weekend as this is the can John reccomends to use. we will see.

this weekend we were out and the snow was fairly deep. my 163x2.5 would not go anywhere near this sled. weather or not its the extra 6" of track on the ground, the better clutching or the engine and possibly a combination i dont know.

i have pulled the plugs once at 470 and it looks like i have room to move. have i had time to fine tune this engine? no.

riding conditions have been to good. this sled pulls 8200 rpm all day long with this clutching and the big track. to be honest the snow has been to deep and avy conditions too bad to do any head to head testing. just going by the seat of the pants feel.

this motor has also been pull and go every day and it now has about 800km on it. it runs like butter smooth compared to the factory engine.



i HONESTLY do not notice a "power" increase with my seat dyno. but i do know that the stock engines would have been struggling big time with these big tracks. we are also running a 174 rev with stock engine and it does not spin this track like these motors do. i personally feel any power increase is being sucked up by the large track.

the question is would you notice a power increase keeping your factory 146? i sure think so. now whether or not its a 3000$ amount of power is debatable.

once the conditions settle down a bit and i get a chance to do some head to head and trackspeed checks and comparisons i will post. i hope to see a couple mph track speed increase. if i do i feel the money was justified. on both sleds i would like to try taller gearing. if i can spin the 19/45 NO PROBLEM i should be able to spin something taller which should result in a higher trackspeed aslong as tthe clutching is still being effficient.

 

[TABSTER]

anyone wanna divulge there set ups... like gears, clutching, jets, shims, clip positions, any timing changes, reflash ecm? Running stock head pipe with a Y pipe and can? or complete twins? Is anyone running just pump gas? no race fuel.

 

[teeroy]

excellent info max....thank you

 

[TABSTER]

Booyaah!...Thats what i'm talking about.....real info, now were on the right track.....High 5 Max.....

 

[Modman]

860 RK Tek, not mine. Runs stronger than you'd think. .....rider prefers it over an 880 and a 1085 that he has in the garage.....

Can get you the specs if you are interested.

 

[teeroy]

860 RK Tek, not mine. Runs stronger than you'd think. .....rider prefers it over an 880 and a 1085 that he has in the garage.....

Can get you the specs if you are interested.

yes please Modman, any info you can provide will be carefully scrutinized. a lot can be gleaned from the setup info....pipe/can info, gearing, added flow from intake mods etc. pinweight and clutch settings, as well as jetting and any shim adjustments. thanks for the response

 

[TABSTER]

Come on guys and gals....we were on a roll... don't stop now....

Good and/or Bad....is all pertinent....