New to the X - Tray Vibration fixed!! now on to carb jetting after mikuni rebuild kit....any input?!

[Cody Sampson]

Hey group , new to X-H2O so forgive me is this post is in the wrong location. Just purchased a 91' SN 701 with the following:
Factory B-Pipe
Wet Jet Intake
Mikuni 46mm SBN??
61x 701


Few questions after the initial ride: Tough to start but runs well once its started, going to do a carb rebuild. Can you tell which carb I have from the pic? I assume its the Mikuni 46mm SBN but not certain.. any way to ID it?
I noticed a vibration under the tray while riding at all speeds.. wondering if it could be mid shaft, bearing, prop... ? any good diagnosis methods,replace one component and ride to see if it fixes it?
Lastly the it seems to bounce off the rev limiter quite early, is this typical for a stock Yami CDI or could something more be going on. Have not torn into it, just looking for advice on where to start!

Appreciate the help!

 

[orangefinger]

for rebuild doesn't matter all parts 44/46 same ....Silver normaly 46 but have seen 44's too , measure bottom hole once u take carb off then u will know

vibration in tray is your knees shacking cause its so awesome to ride a super jet ....

I would check prop...chewed up ? , or damaged mid shaft housing ( rubber part ), bent driveshaft, loose motor mounts

u might not have stock CDI , did u open box and look ?

 

[tor*p*do]

Looks like a 46
Ditch those air cleaners for stock replacements before you such metal mesh into the motor.
Check midshaft and pump seal for vibration.

 

[Cody Sampson]

Appreciate the quick feedback! Sounds good on the rebuild being the same, I'll have it off tonight and measure to be sure.

Ridden many SJ's before just never had the ownership of one, I love it. My new workout for the summer for sure!

Prop looks good nothing chewed up. has a trimmed ride plate and nozzle.. I'll have a look at the mid shaft/pump seal tonight to see if there is any play... had a thought maybe that the engine wasn't shimmed and there is misalignment?

Previous owner said it had an MSD CDI that failed and he put the stock Yami back in but haven't opened it to confirm yet. Seems to bounce early when snapping the throttle up to WOT.

New air cleaner came in the mail yesterday 2" Tau Ceti.

 

[Cody Sampson]

Took the engine forward and felt the play in the couplers engine side and pump side. Pump side had more play (few mms) and engine sounded like there was some play in the engine case when rocked.

Wish I could post the video of it.. Plan to replace midshaft and see if that takes care of the play and vibration..

Sent from my SM-N910V using Tapatalk

 

[Cody Sampson]

Tray vibration fixed! Replaced midshaft from JM. Also the engine was not shimmed at all previously... it took 3mm of shimming after replacing the midshaft. No longer tray vibration!

Now for the other rebuild. Rebuilt the carb and replaced everything and put on a tau ceti tornado 2" air filter with cover. Previously had nothing-previous owner ran without one.
--in the mikuni carb rebuild kit.the (Blue Number two) gasket was not in the carb when I opened it up but i put it in becuase of the picture.. was that right or wrong? Also may have flipped one of the clear discs (check valve-Blue number 1) cant remember.... This may be the cause of the tunning issue.. see below.


Along with the Rebuild
Rejetted from 115P/155M to a 120P/150M (stock)
Went from black spring (XXg - unsure) to 95g spring
Unknown previous pop off - tested after rebuild and new spring ~20PSI - Mikuni recomends 25-20PSI with stock arrestor so I dont believe 20 is unreasonable..?)
Needle and seat unchanged. utilized the existing 2.0
^^These settings recommended by JM-Also recieved all parts for the project through him, awesome help ^^

SO lastly test rode tonight... ran on the trailer and got the idle set to roughly 1250PRM, snapped it a few times felt ok but underpowered.
Screws were set at 1.5 turns out to start... felt very underpowered and not crisp slight lag snapping to WOT. turned the pilot out and tested various turns out... all the way out to 3.5. At this point it was slightly better if anything. Plug was lean looking (grey). Did not go WOT for any period of time all through the ride. Tried to dial in the pilot but unsure where to go from here... up the pilot and richen and work back? Pull the carb gasket out? Recheck disk?

Thoughts?

In general question... rev limiter seems to hit earlier than it should... plugs were new, CDI was a stock yami. What would be next to check? Get a tacometer? Coil? Replace CDI?

I know this is a lot but I appreciate any feedback you have!