lords88
New member
Anybody running a bigger carbs on their mountain max. I am going to put a set of 40mm TM flatslides on my sled. I was wondering what needle nozzle and needle I should start with as a baseline?
triplefastaction
New member
I wouldn't recommend using 40's. I think they're too big for mountain applications. IMO
lords88
New member
It's for my 944 not a stock 700. So the 40's should be small enough. No one one here has used bigger mikunis on there sled? I am just wondering If I should use the Q-0 jet tubes or the Q-4.
Sledsquatch
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I had dual 38's on my old Merc bored out to 40's, it was just a 440. We put in stiffer primary spring to eliminate the low end bog and boom, lots of fuel delivery. Not the same as your application though. But hey, I am bored and wanted to chime in.
lords88
New member
LOL thanks for the input! 
triplefastaction
New member
You have to be careful because big carbs on big motors don't work the same in the mountains as they do back east.
Sledsquatch
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triplefastaction said:
Good call eh. thinner air so maybe a msaller carb will help compress the stuff better me thinks eh. Maybe a larger passage way from the carb to the case would be better.
lords88
New member
No one has any input on there TM flatslide carb setup?
Yamablue
Member
I have a rack of 38mm TMs I had on my Viper that I'm going to get rid of. GOing back to stock, so I do not need these anymore. It is a rack of a 2001 XCR800, so there is a TPS (not that you need it).
lords88
New member
What do you have for jetting in those carbs?
get the best of both http://www.aaenperformance.com/snow_carb.asp
MM800
Member
TMX Carbs
I'm running a set of the SLP (BB) on my 800 BB SLP motor. This was my second ride today since crashing back in 03. I'm gonna jet down in the mains and the pilot. I have always had an issue with getting the idle just right. I could never get it lean enough. At this pont the idle screws are set high enough I think I have completly passed the pilot circuit. I have never had the stock carbs on it since I built it in 00. I used to ride at 8-10000' Now 6500 is max and I unload at about 3000. I also run an ATTAC. I'll know more in the next few days as I break things in from the long wait. Started out running pig fat and I'm slowly going down. I think I'm running 400 mains, 56 needles and 55 pilots. Mains can come down, maybe 2 sizes and maybe try one size on the pilots. It rreally zings in the middle so may have to lower the needle once I make the other ajustments.
I'm running a set of the SLP (BB) on my 800 BB SLP motor. This was my second ride today since crashing back in 03. I'm gonna jet down in the mains and the pilot. I have always had an issue with getting the idle just right. I could never get it lean enough. At this pont the idle screws are set high enough I think I have completly passed the pilot circuit. I have never had the stock carbs on it since I built it in 00. I used to ride at 8-10000' Now 6500 is max and I unload at about 3000. I also run an ATTAC. I'll know more in the next few days as I break things in from the long wait. Started out running pig fat and I'm slowly going down. I think I'm running 400 mains, 56 needles and 55 pilots. Mains can come down, maybe 2 sizes and maybe try one size on the pilots. It rreally zings in the middle so may have to lower the needle once I make the other ajustments.
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lords88
New member
Well I put my 944 together tonight and I put 40mm TM flatslides with powerjets, with Q-0 needle jets and 6dp4 needles set at 2nd slot from the top, 45 pilot jets, and 350,360,350 mains to start with(counting the powerjets.) I ran it on the stand and it idles fine but looked pretty rich at around half throttle. This is all at 5,500 feet. I am hoping that when I get back to Moscow this weekend there will be enough snow to ride. I cant wait to get it out and ride.
MM800
Member
Tmx
Mine are TMX carbs. The needle jets are fixed and you can only change the needles/slides to calibrate the mid lower end. Just switched to 290 mains tonight. Had 310 after second ride. Going tommorow! Got to find out. How much weight can u pull with that 944. Stock MM weights right now.I'm prretty close to 50 grams with a 52/48 roller on it. Running w/w/w spring. Had a 48/42 with richer mains and over reved a little over 200 rpms past peak. Sled should run 8600-8800 and I could get 9000-9050 pretty quick
Mine are TMX carbs. The needle jets are fixed and you can only change the needles/slides to calibrate the mid lower end. Just switched to 290 mains tonight. Had 310 after second ride. Going tommorow! Got to find out. How much weight can u pull with that 944. Stock MM weights right now.I'm prretty close to 50 grams with a 52/48 roller on it. Running w/w/w spring. Had a 48/42 with richer mains and over reved a little over 200 rpms past peak. Sled should run 8600-8800 and I could get 9000-9050 pretty quick
lords88
New member
I ran 56gram weights last year before I had it ported, upped the compression and put on the 40's this fall. Now I am hoping to pull atleast 58 maybe 60 grams. I will be running a stock secondary with a shockwave helix and black/pink spring set on 70 deg. This will be my first setup to check. I also run at 9,000rpm with this engine.
MM800
Member
Greetings
Just got back from short ride. Still pulling a little over 9000 rpm with the 52/48 helix. Temps are still low. Peak exaust on about 600 yard pull was 1148. Water temps never got over 129 degrees. Most time between 105 and 115. Gonna drop the mains one more . Running 25% race gas, may try less. Not seeing any signs of detonation. Still pretty rich in idle range but cleans up quick. Gonna drop fron 55 pilots to 50s and go for a ride.
Just got back from short ride. Still pulling a little over 9000 rpm with the 52/48 helix. Temps are still low. Peak exaust on about 600 yard pull was 1148. Water temps never got over 129 degrees. Most time between 105 and 115. Gonna drop the mains one more . Running 25% race gas, may try less. Not seeing any signs of detonation. Still pretty rich in idle range but cleans up quick. Gonna drop fron 55 pilots to 50s and go for a ride.
lords88
New member
Hey MM800 where are you riding at? I am headed back up to Moscow from southern Idaho tomorrow and wouldn't mind getting in some riding. I need to get my sled tuned in too lol.