• Don't miss out on all the fun! Register on our forums to post and have added features! Membership levels include a FREE membership tier.

SHR860 vs RK860

winter brew

Premium Member
Lifetime Membership
Nov 26, 2007
10,016
4,332
113
56
LakeTapps, Wa.
Ummm...your brother bought the kit, rode it all winter...you buy sled and ride it the second winter and it goes down...you send it back to "get fixed" not a qoute...I fix it, update the cylinder porting for free, and the pistons/chrome for just above cost (you couldnt have done it cheaper locally)... and you come on the open forum and complain???...what did you want me to doo?? wty a 2 year old mod motor?? doo wouldnt have wty'd a STOCK motor unless you BUY an extended wty...

I guess its true...a guy cant please ALL the people ALL the time....but dont for 1 second tell me I dont try...BJ

TJ- if you knew half the "techno factoid" crap you spout I would be impressed...the 13-1 RKT head works at 400' elevation for 3800' pulls on 92pump gas...as in 125 mph plus pg trail SHR860R sled...



There are some people you don't want buying another motor....sounds like you handled it reasonably :beer;
Put 20 road miles on the 860 Friday night.....so far so good, tough to gauge anything with the amount of snow we had, couldn't hook up to load the engine.....the couple times it did hook it felt nice, I do have to add a little pin weight. That is a good sign. :)
 

BossRev

Well-known member
Lifetime Membership
Dec 8, 2004
8,189
5,415
113
Pleasant Grove, Utah
Put 20 road miles on the 860 Friday night.....so far so good, tough to gauge anything with the amount of snow we had, couldn't hook up to load the engine.....the couple times it did hook it felt nice, I do have to add a little pin weight. That is a good sign. :)


Also put on 20ish miles Saturday. Really low conditions not much of a bite to load the motor down. Found a few spots with a decent amount of snow so I could hammer down. On my stock motor I was on clicker 4 at 9200ft. With this motor, I doubled up the pin weight over stock and was on clicker 2 at 92000ft. In the few spots that I could load the motor it really felt good. This was more of a make sure everything was button up ride then a real test ride but it felt real good and it is very promising. :cool: should have a couple more feet on the hill by this Friday.
 

BIG JOHN

Well-known member
Premium Member
Nov 26, 2007
1,953
1,146
113
Minnesoooota
Most engine builders are using Cat pistons in their big bore engines. 85mm bore 22 mm pins, going to caged bearings to handle the larger pin size over the 21mm doo pin.

BJ man up and post a dyno sheet lets go already. 13:1 won't cut it on the trails and lake racing big guy nice try, especially at or near sea level AND on pump gas.


Darn it... I wonder if ALL the 13-1 860's out there will stay running?? I better change that since TJ said so...LOL

I offer a 12.5-1 for customers who KNOW they have poor quality/low octane fuel...13-1 is just fine for any/all who run 91-92 octane pump...:rolleyes:-BJ
 
T
Nov 27, 2007
229
143
43
Canada
Think about this the head setup on a stock XP and the bowl design.

Now look at what the big bore heads are like and what they are doing. IMO the heads are not as efficient hence the need to jet down or run high compression.

The reason they get away with less jet and more compression is less efficiency and heat in the engine.
 

winter brew

Premium Member
Lifetime Membership
Nov 26, 2007
10,016
4,332
113
56
LakeTapps, Wa.
Think about this the head setup on a stock XP and the bowl design.

Now look at what the big bore heads are like and what they are doing. IMO the heads are not as efficient hence the need to jet down or run high compression.

The reason they get away with less jet and more compression is less efficiency and heat in the engine.

I hope you are joking. :confused:
 
S
Nov 26, 2007
1,664
166
63
Helena, MT
Boy it never fails, one peep on here with total misinformation thinks he knows better then the guys who build and design them.
Dewd go onto RKT's website and it will explain to you how the dome design works. He's been using this design for a long time so if it didn't work don't ya think he wouldn't be making them anymore???
You really look like an idiot since your arguing with the guys who probably know the most about a Doo motor on here.
 

Leaf27

Well-known member
Premium Member
Oct 24, 2008
1,227
694
113
Boy it never fails, one peep on here with total misinformation thinks he knows better then the guys who build and design them.
Dewd go onto RKT's website and it will explain to you how the dome design works. He's been using this design for a long time so if it didn't work don't ya think he wouldn't be making them anymore???
You really look like an idiot since your arguing with the guys who probably know the most about a Doo motor on here.

And the countless guys that run these non effiecient/power BB year after year. That is one hell of a marketing scheme you have BJ.
 
D
Jul 4, 2001
878
262
63
Central Alberta, Canada
Think about this the head setup on a stock XP and the bowl design.

Now look at what the big bore heads are like and what they are doing. IMO the heads are not as efficient hence the need to jet down or run high compression.

The reason they get away with less jet and more compression is less efficiency and heat in the engine.

Officially the dumbest post I've read since 2003 when "Phatcat900" was "helping" everyone tune their 1M's.....congrats.
 

High Voltage

Well-known member
Lifetime Membership
Jan 30, 2003
2,541
3,220
113
Helena, MT
Think about this the head setup on a stock XP and the bowl design.

Now look at what the big bore heads are like and what they are doing. IMO the heads are not as efficient hence the need to jet down or run high compression.

The reason they get away with less jet and more compression is less efficiency and heat in the engine.

Please donate your brain to science. being you are not using it!!! LOL :rolleyes:
 
S
Nov 26, 2007
1,664
166
63
Helena, MT
Obviously this guys isn't going to be happy no matter what anyone tells him. He wanted Dyno numbers, got them and is still complaining.
You know he isn't going to buy a BB so what's the point of arguing with the guy.

Oh and Turbo Mouth, way to ruin a guys thread that just wanted to know about a BB for his sled, I hope someone can do the same for you when you have a serious question.
 

byeatts

Well-known member
Premium Member
Nov 29, 2007
3,403
1,215
113
What didn't you like about your SHR 860 that you considered it a waste of $$?? :confused:

I have a stock 800 and a 880 and 860. There simply is no comparrison of theses motors. I ride the stocker when Powder isnt deep and really dont need all the HP..BJ,s workanship and service have been second to none. However your really need to have the BB,s setup correctly to relize the benifit from the extra CC,s. Its really like comparing a 600 to a 800 when running a properly setup BB. First hand observations!
 
S

shortstop20

Well-known member
Nov 26, 2007
2,595
209
63
South Dakota
I'm going to get my sled dynoed and get the curve and peak HP numbers plastered on a big sign welded to the rear of the tunnel, like 4'x8'. With all of that drag I'll get beat everytime, but at least everyone will know how much HP I got! :rolleyes:
 
C

CBX

Well-known member
Jan 21, 2008
492
187
43
Oh TJ, I could go on and on, but your last post says it all.

You do realize computer modeling goes into these designs right? Do you truly even understand how a 2 stroke works?

Do you understand how a carburetor works?

Just asking...
 
Last edited:
Premium Features