Drwe
Member
- Joined
- Nov 28, 2021
- Messages
- 75
So I took the warm day as an opportunity to clean the carbs for the first time since I purchased my 1998 700 vmax last season. I have found that the Mag side carb has 145 main jet while the others have 143.8 (if I can read the text correctly) all 3 have 45 pilot jets.
Why would one carb be jetted differently, is this likely intentional or did someone just rush out and replace one of the jets with another on hand?
I may have been too careless and not carefully counted the fuel screw turns (lost count) on the first two, though I think they were probably just over 1 1/2 turns out. The clutch-side carb had 2 turns out.
I did foul a few spark plugs last season, a couple times when warming up the machine for a few minutes and once on the trail. I forget which cylinder it was but one of them definitely looked richer than the others on a consistent basis (wet spark plug). I am new to sledding but power seemed pretty good all last season.
I'm about to throw the carb back in the sled but I wanted to see what people would suggest for both jetting and fuel screw turns. I was considering putting them all to 1.75 turns out (more rich than 1.5 for safety but not quite 2). Or I could use 2 turns for the clutch side since I know that is what it was at before, and set the others to around 1.5 turns.
Why would one carb be jetted differently, is this likely intentional or did someone just rush out and replace one of the jets with another on hand?
I may have been too careless and not carefully counted the fuel screw turns (lost count) on the first two, though I think they were probably just over 1 1/2 turns out. The clutch-side carb had 2 turns out.
I did foul a few spark plugs last season, a couple times when warming up the machine for a few minutes and once on the trail. I forget which cylinder it was but one of them definitely looked richer than the others on a consistent basis (wet spark plug). I am new to sledding but power seemed pretty good all last season.
I'm about to throw the carb back in the sled but I wanted to see what people would suggest for both jetting and fuel screw turns. I was considering putting them all to 1.75 turns out (more rich than 1.5 for safety but not quite 2). Or I could use 2 turns for the clutch side since I know that is what it was at before, and set the others to around 1.5 turns.
Should say on the clutch guard for the pilot screw settings, but I'm sure 1.5 is stock.
145 should be in the PTO cylinder, or otherwise known as cylinder #1
145 should be in the PTO cylinder, or otherwise known as cylinder #1
Drwe
Member
- Joined
- Nov 28, 2021
- Messages
- 75
Thank you, yeah sorry, I was calling PTO side clutch side.
Why is the jet different for this one? I now see the manual calls for 145 in #1, and 143.8 in #2 and #3 as you say, so I will move the 145 over to carb #1 (previous owner must have put it on #3, Mag side)
If 1 1/2 turns is safe for all, I guess I will just go with that.
I imagine this can only help my performance. I am installing reed spacers also, hopefully she will run better than ever.
I think that cylinder must run a little cooler and then needs one size more.
The fuel screws only affect idle mixture and up to 1/8 throttle opening. No effect on full throttle mixture.
The fuel screws only affect idle mixture and up to 1/8 throttle opening. No effect on full throttle mixture.
it was nesasary on the tripples with even compression to jet up that one cyl. all the sx and srx tripples where that way. the sx viper actually had lower compression on that cyl by 10 lb so that they could run square jetting.