main jets on stock 93

[dreaming-of-a-v-max-4]

any of you guys that own a STOCK 93 know what main jets you are running i am running 147.5 in mine seems kinda rich to me it let me know what the stock ones are and what you are running i know they came rich from the factory thanks guys for your input
later tim

[AL P]

I believe your 93 came stock with 135 mains, and 47.5 pilots. 147 seams huge to me, my 95 800 only runs 143.8`s stock.

[dreaming-of-a-v-max-4]

i must have removed the wrong one witch one is the main i cant find my manual any where and i am lost with out it thanks for the input al i will go check again

[AL P]

its the large one in the center, the pilot is the little one and its in a tube

[dreaming-of-a-v-max-4]

i see where might the jets be marked i cant find any #,s on them anywhere i will go look again thanks

[dreaming-of-a-v-max-4]

i found it i have 140 main jets and 47.5 secondary last season my plugs were pretty black and it was real sluggesh on take off so i am turnning out my air needle to 1.5 turns insted of the 2 it was set at but i still need some main jets any suggestions on the mains should i go with 136 or less or start at 140 and go down one size at a time last year i had a gutted air box (that was all i had at the time) this year i am putting a stock one in it any suggestions would be apreciated thanks tim

[RDL 93 V-MAX4]

Have my manual here it says the falowing:

Carburator Tuning Data:

Model TM33 x4

Manufacturer MIKUNI

I.D Mark 89A-00

Main jet (M.J.0 #140

Pilot jet (P.J.) #50

Jet needle (J.N.) 6GN14-3

Float height 11.3 ~ 15.3 mm
(0.44 ~ 0.60 in)

Idle Speed 1,400 ~ 1,600 r/min

[dreaming-of-a-v-max-4]

thanks is your sled still stock are you running the 140 jets in yours

[RDL 93 V-MAX4]

I have 137.5 in my sled. Had some issues last season with plugs was running too rich. The problem was that my choke was to say partially on. Had to loosen the tension on the cable. Seam to run alot better for a few weeks. Then was foulling some plugs again had BR9 NGK's in it at the time. Just for kicks went to BR8 plugs and for the rest of the season never fouled a plug. Checked them often and they were golden brown vs the 9's that were often black and wet. Also had the air screw turned to 1 1/2 turns out.

[AL P]

Humm,,, the yamaha site list the 93 & 94 as using a 135 main, and 47.5 pilot both bieng the "standard" stock. They list the 92 as using a 140 main, and a 50 pilot as bieng the "standard" stock. dont know if they listed them wrong or what, but thats what I was going by. it seams to make sence bieng the 92`s were a little differant than the 93 & 94, becuase of the port timming. AL P

[J-Max4]

I have 133,8 in my stock -92 and it have worked fine. I think that you should try 135, if your sled is stock. I have done some porting to my cylinders and i use one layer head gasket now so i am going to jet up to 137,5.

Juha :i_need_sn

[IZZ]

Hey Tim, If you gutted your airbox last year and didnt jet up the low speed circuit, the reason your sled was sluggish off the line was a lean condition. I tried the same thing. It ran too lean at low speed with a gutted airbox, would sort of fall on its face before taking off.

[dreaming-of-a-v-max-4]

yes it was gutted but that is the way it was i did not gutt it out but your right it would fall on its face if you hammered it but if you eased into it a litle it would be fine but to set there and idol it would fowl plugs so i thought i would get it right this year thanks tim

[toydoc]

The first year 1992 Vmax did come with 140's. Thats correct A/F for the engine when yamaha tested on the dyno. But they didn't perform correct in the on the trail, they ran rich. Then dyno-tech found the underhood pressure issue. Next year yamaha drop to 135mj. But that was so lean on a dyno it had a hard time making power to even spin the dyno. But with stock under hood pressure the 135mj was fine for trail riding.

Stock 93 for 0~600'
137.5 good -4* ~ 32*
135 good 20* ~50*

IMO, I'd never go hotter then factory spec for spark plugs. If all the other sleds can run stock heat range for years without fouling but your sled can't. Somethings not right and needs to be corrected. When you go up on the heat range it just open yourself up to many other poss bad $$$ things.

[RDL 93 V-MAX4]

This week pulling carb rack off for their yearly cleaning. Once done will put the BR9's back in and see how the plugs look.

[MadMax-4]

Hey All,

I have been running my Max with the following jetting for the past 10 years with no issues

Main Jets #135
Pilot Jet #47.7
Air screw 1.5 turn out
Vent tubs pluged into air box.
I have run my Max at WOT meany times at runs of 10 Km + with absolutly no issues

MadMax-4

[dreaming-of-a-v-max-4]

i think i will start out with the 137.5 mains and air screw out 1.5 turns thanks for all your great advice
later tim