8BU-10 setup ..round 1

bluemonster1

LIFE MEMBER ONLY ONCE!!!
Joined
Dec 30, 2005
Messages
12,690
Age
68
Location
Howden ,Manitoba,Canada
8BU-10 setup ..round 1 and round 2

well took the SRX out today for a good 27 miles on the River.There are a couple good spots to open it up but with about 2 to 3 inches of snow on top,not really packed down good yet.
Temps are cool like around -14 C here and sunny with 73% humidity today.This is my real first attempt with the 8bu's.I have the weights at 2.4 inner and 3.6 outer using a w-w-w primary spring with no engagement springs.Engages around 4000 rpm's.In the 2ndary I have the 50/40 helix with red spring set at 80.Seems to pull nicely,spinning a lot at take off because of loose snow yet.When I pin it..goes to about 8400-8500 and was hitting 105 on speedo the rpm's dropped to about 81-8150ish and no more.This was on the River with the snow.Tried another spot along the floodway that was groomed,loose snow and with only limited length because of corner coming up ,was hitting 95 and rpm's were about 8400.The snow is the factor here..but I think I need to try the green spring at 80 next to see what happens.On ice would of been a differnt story with less drag.
 
Last edited:

oh ya..checked my clutches a couple of times after a few wot runs.Clutch's are totally on the cold side..no heat at all present.So I guess the belt is grabbing and not slipping creating heat..that is great to see.
 
try it with the green spring ....if the rpm still going down at top end u will need a smaller finish helix or take some weight off tip
 
stock gearing,with Predator 1 " track with 120 1.075 studs.I know I can't compare to others who run there SRX's on ice,low paddle track and 192 chisels,lowered chasis,light rider and 1/2 gallon of fuel in the tank.Just aiming for that magic 8400 rpm range wot.
 
Keep us posted. Last year I was hitting 111 on speedo on warmer temp day with grainy snow, 106 gps with loaded 8dn-20 with 52-46 helix and red spring at 80, but only pulling 8100 rpm, need to wind the sprig to 100 or try green at 70 next. Going to test that and then stock helix and see what speeds I'm pulling. Speedo not working this year so only gps speeds :) key broke off in driveshaft. Might fix next summer. But I know it'll be running some good speeds! Gotta beat up on a xcr 800.... Hopefully
 
bluemonster1 said:
I am going to hit the river again in a bit,changed red to green spring..still at 80 wrap..we'll see what happens..



go blue go bad i'm not there to do race with ya
 
Spinner18 said:
Keep us posted. Last year I was hitting 111 on speedo on warmer temp day with grainy snow, 106 gps with loaded 8dn-20 with 52-46 helix and red spring at 80, but only pulling 8100 rpm, need to wind the sprig to 100 or try green at 70 next. Going to test that and then stock helix and see what speeds I'm pulling. Speedo not working this year so only gps speeds :) key broke off in driveshaft. Might fix next summer. But I know it'll be running some good speeds! Gotta beat up on a xcr 800.... Hopefully
need to remove some weight in primary never adjust the rpm with secondary
 
Set up

Where did you get the initial set up? It is very different than what I remember running with those weights. Have you sent a PM to Yammigod316? I know he's been playing with those weights lately. And lastly....are you sure the sled is finally running right?

Madmatt
 
Hey blue, we need to meet up some time. I am on the north side of the floodway and you are on the south. I have really enjoyed reading your numerous posts and now have mouse traps around my sled at all times. I have recently changed my stock clutching on my 98 srx700. I have purchased the 8dn-20's and the 89a-10's and I have the 8bu-10's coming. Bought a Dalton 53-43 and looking for a second helix for the 8bu-10's. Tuning clutches is a hoot, (like doing a logic puzzle, but way better cause the result is speed). Any chance you'll be at Beaver Days on Falcon this year?
 
Hey Paul..we could meet up along the Floodway system 1 weekend.Went up that newly dug channel now and it is smooth.We only went as far as #1 Hwy only.But it will take us all the way to Lockport if we wanted.A real good place to take out an SRX and pin it for more than a mile and smooth ice with little snow on top..unless all that wind we had drifted it all in... #$%&*
 
ok mod..with the green at 80 I did get 8500 rpms at wot,but my speed dropped some..didn't like it.BUT the midrange pull is wicked man... ;)! My next move might be is to go back to red spring at 90 wrap and see if I can pu some rpm's.
 
sled is running the best I can get it.Only have like 520 miles on the rebuild,maybe rings aren't still broke in all the way yet. Starts really good now,outside today in -14 C..choke and 3 pulls.3 pulls inside also.Used to take anywhere from 6 to 10 pulls before .She is more snappy now and that flat feeling when pinned is gone,winds right up.Who knows.If the 8BU's don't satisfy me,I will put the 8dn's back in..tried and true.Then sell the 8BU's to Tony..lol he wants them bad for some reason..lol
 
Last edited:
have new spark plug caps coming soon.I ohm'ed my caps..i showed a slight movement on the needle,the other 2 show nothing.Maybe this will help out also..worth a try.
 
Hey blue why not try that green at about a 60 wrap? See you can get that thing to fly? What are your lines in your clutches like with the green at 80? Did it shift out all the way?
 
the primary lines I made have about 1/4" black marker left..so belt is climbing to the top,thinks the green was to much pressure at 80.I will try red spring at 90 first,I red spring seemed to be more suited I can see.There are different combo's to try and only so much time to ride..Tomorrow is another testing day I guess.
 
yep i would try that green spring with less twisting around 70 ..to mutch twist will take more place to get full speed .......
 
Oh I think you are knocking on the door but like mod says the primary tip might be the best thing to start with and if your red at 80 isnt slipping I wouldn't change much from where you were. Like I say maybe a green at 60. Thats all.....testing is where the funs at. Good luck...we will be watching!
 


Back
Top