Rehabbing A Rebuilt '99 700 Triple - Dies w/Choke

@MURDER YAMAHA it was kick ass. Keep the old sled dream alive.

I ordered a set of adjustable weights that indicated they'd fit the 8mm pins on the primary with a 50g base weight, I'll play with it until we're in that 8500 range.... it's peaking at like, 9700 right now
 
The longer 151 track length might have something to do with it b/c I didn't swap gearing or the track drivers etc... I would think I'd feel that more as bogging down / loss of RPMs on those steeper hill climbs
 
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morecowbell said:
@MURDER YAMAHA it was kick ass. Keep the old sled dream alive.

I ordered a set of adjustable weights that indicated they'd fit the 8mm pins on the primary with a 50g base weight, I'll play with it until we're in that 8500 range.... it's peaking at like, 9700 right now
Click to expand...

Oof, I think I'll be under 50 on mine even after I get the rivets in. Is that the Thundershifts? They used to make lighter ones.
 
Lightest ones I could find that explicitly said they'd fit the 8mm pins for the primary but i'd order something else if y'all have a recommendation. They're the STM Supertip Trail Cam Arms.

9gr difference between them and current arms but I dont have a way to add weight and I'm way, way above the RPM goal. ....

Secondary position is 6/1 with a green spring, btw.
 
Update. The 50gr weights felt a little bit sluggish for power. But the Tach was topping out. So I began to suspect the tach itself. The dash pod is ported from a 1998 MM 700.... the original dash with the two separate round pods was trashed when I got the sled. So I grabbed one of those cheap "tiny tachs" from amazon that you wrap a little interference cable around a spark plug wire.

Turns out there is a pretty significant difference between that tach and the one in the dash. When the tiny tach reads ~1500 at idle the dash says ~2500.

So now we get to try again and see what the tiny tach tells us 🙂

'Course now all of the dash pod indicators are suspect, lol. The fuel level, speedo, brights indicators all seem to work. I've never tried to trigger the water temp indicator or the oil level indicator lights.... i put new sensors in during the overhaul and have always treated it mostly nice. Not sure how I would test those realistically. Can I just unplug the clips and complete the circuit?

EDIT: Yes, you can short the sensor plugs and it will make the dash pod lights work. So everything but the Tach is happy. Now we just need to dial it in!

EDIT: After some Google-fu it looks like the 1999+ has a 12-pole stator but the 1998- had a 6-pole. So the tachometer for that older sled is reading basically double the real RPMs which sorts explains everything. I'm also gonna find some kind of frequency step-down unit.... and it should get the original tach working right again... Because, nerd sh*t I guess
 

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@MURDER YAMAHA @sideshowBob -

Back in Cooke. Having this one side-by-side with the other MM 700 here and the highway to blast full throttle up to compare is helpful but is revealing this sled still has more demons.

Long story short - she starts just fine after a few pulls with choke. Idles fine at 1500rpm forever once its warmed up. Seems to be plenty happy at low-to-medium RPMs but the top end just is not there at all. The other MM 700 is straight up scary to full blast on the highway and has noticeably more power at the top end when blasting hills.

Mine almost feels like it's running insanely rich when you got WOT, and it won't rev past maybe 6000 (hard to tell with the sh*t tach the way it is).... It just does not scream the greasy triple scream the way the other one does.

The sled is as described above, #135 main jets, #55 pilots, 2 screw turns out. Maybe a touch rich on the jetting chart all the way up this high but no way it should stumble the way it is on the top end. Brand new WSW main spring with stock 41gr 8CR weights in there. Brand new green secondary spring set at stock 3/3 settings.

The engine has those replated cylinders, brand new pistons, rings....

What we've done:
- New in-tank fuel filter / line
- Moved secondary preload around
- Swapped clutches completely between the two sleds
- New belt
- Full tank of pure give you cancer immediately mineral 2 stroke oil
- Deep cleaned the carbs (incl needle)
- Cleaned / new BR9ES plugs
- Moved the position of the spark plug wires to each cylinder (no difference)
- Confirmed each cylinder has spark (and actually will run with the other two unplugged with a bit of throttle)
- Confirmed throttle position at WOT is in fact pulling the throttle to the WOT position
- Confirmed the choke is NOT too tight (or stuck)
- Blipping the choke at WOT adds too much fuel and it stumbles more (no improvement)

These have produced at best very minor improvement...

Do not have a compression gauge with me or a way to leak-down test but we cannot for the life of us think of anything else to try? You Yammie warlocks have any bright ideas??
 
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