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Discussion Starter · #1 ·
Hey everyone,

Thinking back on last winter, most riding days for me were at freezing temp or above. I also rode(like alot of us) a few days where the temp might have been around 36-38 degrees f.

My 2002 MachZ Standard is bone stock with about 800 miles on it.
Most of the riding kinda felt sluggish.You know when the snow is wet or if it lightly raining. Does jetting lower really make a noticable improvement if temp is warm and humidity is high? I say this because there was this one morning I went out early (temp at 21) and there was a considerable difference in response. The response was crisper and the smell of the exhaust was even different! I know given the fact that the lake surface was hard packed and completely frozen that morning, traction was excellent., but it excellerated that cold morning 0-80 mph in such a way that you get that butterfly felling in your stomach. You know what I mean?
If temp and rh (relative humidity) have such a profound effect on performance can I jet down and how much. My dealer (HB Cycle Lindsay) says that there is room for one step from stock. Stock has the jetting set for optimum performance at minus 18 degrees celsius.(what ever that is in farht) .
To me that is pretty cold to enjoy a ride at optimum performance.
What if this winter is also a mild winter?

By the way, I always run the Sunoco Ultra 94 octane gas and have 144 studs. On the trails my plugs always look black and wet. They only look brown after a good shot on the lake at wot. Top speed is 189 km.
Have you guys jetted lower on the 2000-2002 triples?
 

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no i even run stock jeting in the  summer . when it is realy hot in the summer i will go down 2 sizes but thats just my little thing.....hehe  i dont realy think it does much . so no u should have to jet down. r u running any type of exaust tip or just stock. if all is completly stock u could check your oil injection setting to see if the lines line up sometimes they will be set a little richer. and also the sluggish fealing could be cause of water in the gas but there is a big difference from soft snow and hard when it comes to studs ....i know .lol i to runn 144 and if its soft lots of sleds could run with u for a short time but when its cold and hard snow it will rip youe arms off......lol so again dont bother jetting   ...suspention....suspention....its does pay off when properlyset for the conditions
 

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They say: for every 20 degrees in temp diff. you can change 1 size. Example with stock jetting say good to 0 would be, 0-20 above drop 1 jet size, 0-40 above drop 2 and vice versa.
If you run 3/4 to wot the main jet will improve some responce and mileage but anything under that your needle position will make a bigger difference. Changing needle position in a Mach is a real hassle, if they had the mick's like a polaris edge it would be a breeze! I dropped my needle 1 position and left it there all last winter just because my mileage was so poor and gained 2 MPG by doing so. $hit man it's a MachZ, you only need 1/4 throttle to go 80!!
 

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The best thing you could do is buy or at least check out the Holtzman tempa flow. At a radar run last year the temp started out at about 20 f and got up to the high 30s in the afternoon,my plugs looked great all day ,my buddies t cat started out the same but by the afternoon was leaving carbon on the ice for ten feet.Very simple mod,but your air box will take a bit of a beating while getting it apart.
 

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The easy fix you need is to drop the pilots from 50s to 45s. Leave your main jets stock. This will fix your plug problem and your sled will run like it should. The mains are plenty lean, in fact I'm going richer one size as the stock mains are lean even in warm weather riding (30F). The main problem is at idle in warm weather, it is just way too rich. Your oil pump setting should be stock. The pilot change will really clean up those plugs. Good Luck!
 

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Discussion Starter · #6 ·
thanks machz69, Mikadoo and John,

I think after reading some great carb tuning info from you guys I am getting this carb stuff. Thanks for the
advice to leave my mains at stock settings. I agree because I can see why at wot my plug test is shows a nice brown colour.

Question for Fast Mach Z, is the pilot change something I could order the parts and do myself? Does a pilot change effect only the idle or also up to 1/4 throttle positions?
I want to lean on up to the 1/4 throttle area because this is where most of the slow forest trail riding plug fowling occurs.

Have you dropped the pilots from 50s to 45s in yours?
Did you change needle jets or the jet needle positions at all?


Where can I find a diagram of these mikuni flat-sided TM 38mm's?



Thanks
 

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If you want to look at a quick reference or exploded view go
over to ronnies.com and click on OEM PARTS. In there you'll
find digrams of the whole sled and OEM part #'s. It only goes
up to 2000 but you'll still see a diagram of flatslides. Or you
can get Aean's Carb tunning handbook or SDoo CD-ROM which
will have everything you'll need. Good luck
 

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yeah if u go down it will effect from iddle to 1/4 but it also does effect the total mix. if your just looking at your plugs and the top of your pistons dont forget the oil u run plays a big part here. if u run klots u wont even see a partern it will look like wash. some other oils such as oem oils will have more of black look  like a lean condition. if u are running a mach u will not notice much of a diff. bue if u have round slides then yes u will and a temp flow is a good add on but  again not for flats slides. save your $$$$$ and time
 

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</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">
Where can I find a diagram of these mikuni flat-sided TM 38mm's?
[/b][/quote]
Someone mentioned in another thread that Mikuni's web site has tons of valuable info.
 

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if your going to play with jets, why not throw some mod pipes on her? if your going to play play hard. pipes jets and a good clutch, that will smooke all the rats
 

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I have found that dropping the needles one groove really helps clean things up. Gas mileage will go up, crisper throttle response, etc. A word of caution--Check your plugs after running low to midrange speeds. If they are white, you're are running to lean and could burn down your engine. Chances are, it will be just fine. I lowered mine one groove three years ago in West Yellowstone and never put them back. I ride at less than 1000 ft at home and the plugs a a nice brown here. I believe I could drop the needles one more groove for
altitude riding. My mileage went up 3-4 mpg. I don't really know why it says NEW RIDER over on the side--I've been riding since 1966!!!!!
 

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Dito what snodrifter says
 
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