YICS

Hoppes #9 gun cleaner solvent works great on cleaning the YICS passage.......

 

And afterwards, pack some black powder and a cap way down in there, and give that bolt a tap! haha.

That oughtta clear it! lol

 

Cleaning the bore ain't the prob', it's getting up into the ports & I bet most DIYers don't.

 

So technical... yes, cleaning the bore AND the holes IN the bore.

Still, you can't go all the way in the holes anyway.
Can't really get at those with the motor all together, at least past the first bit that you can get a bent piece in.

 

OK, now I feel totally lost. I know the YICS passages on the 550s are different somehow (you don't need one of Lens's special tools) but how/why do they get clogged up? They're on the intake side; all that ever passes through them is high-velocity fuel-air mixture which I would think would be the equivalent of aerosol carb cleaner. How does enough "dirt(?)" get in there to clog them up? Every time I've had my 550s open and stuck a Q-tip in there it's been clean. Is this a "sitting" thing?

 

The 550 YICS intake ports are HUGE compard tot he 650-up ports, which are tiny........

 

Yeah, mine are barely visibly really. I mean it is hard to tell that far in, but they are probably (from what I remember) smaller than the stick part of a QTIP.

 

they are. even smaller than a tooth pick.

 

- just done a quick explore and the 400 passages can certainly take bigger than a toothpick. YICS passage is clean as a whistle though. As 'fitz said, can't see what could block them.

 

Late to this thread but, thought I would add the YICS bikes do seem to get better milage.
If you look back through the many "What milage do you get" threads, it is pretty clear that YICS bikes are ahead in this aspect.
From what I've seen the 650 Seca's usually come in at 35-40mpg.
Where as the YICS bikes get closer to 45-50mpg.

 

Heck,
My 750 YICS Maxim is getting between 45 and 53 mpg, for the last 5 tankfuls, depending on how i ride it.

Knock on wood...

 

Well said, Hound, but the thread was about was the YICS tool neccessary when syncing the carbs.

 

Heck, hound, pay attention! hah. jk!

Has anyone here (Fitz?) done the test to see what difference there is doing the COLORTUNE with and without the YICS tool, yet?

 

I will be but my homemade YICS tool died and I havn't got my next order from chacal pulled together yet.

chacal's discovery of the reference to the use of the tool for EGA adjusting indicates Yamaha believed it to be necessary; I am quite curious to find out exactly how much difference it makes in THAT PHASE of tuning.