Shaking 61x....is this too much vibration

[adamrs80]

I'm trying to determine if there is something wrong with my engine or if this amount of shaking is normal. To preface, this is my old engine completely rebuilt, new crank, bored to match the new pistons on Aqua's old ported 61x cylinder. It has about 5 hours on it and it's probably running a little rich. Single 44 sbn, 80 gram spring, stock needle/seat, 125 pilot, 150 main. 1.25 turns out on low, 1 out on high. Pop off should be around 38 psi. Factory type 4 dry pipe, FS sport ported, R&D rec. head.

The motor mounts are brand new, and I was very careful when I reinstalled the engine to get it level and straight with the coupler. It just seems like is vibrates alot. Of course it smooths out when it revs up. Does this look normal to anybody? The metallic knocking sound should be the drypipe hitting the inside of the exhaust manifold.

Take a look.....please give me your thoughts, I'm supposed to go riding tomorrow but I don't want to cause any damage
[ame="http://www.youtube.com/watch?v=iRv99NZCkc0"]YouTube - superjet 61x ported type 4 drypipe[/ame]

 

[Kennay]

hard to tell with the low frame rate... dramatizes it a bit. I'd say it looks fine.

 

[suva]

My brother's ski shakes a lot, maybe not quite that much, but quite a bit and it's been fine. He's running a type 4, stock porting, 180psi and dual 38s.

 

[BombThreat]

ditto, mine vibrates like hell if i have the idle set real low..

 

[Etheraldreamer]

low idle makes mine sound like its camming like a muscle car. lol and the motor shakes even worse than yours. its fine though. or at least it has been for a number of years

 

[Johnny340]

That F/A accentuates the vibration too. If you are sure that metallic noise is the pipe then you're probably fine. Just pin it!

 

[adamrs80]

Awesome, thanks so much guys for the input. It's nice to have somebody else take a look at it. What a relief.
I agree, that F/A is pretty tall and must make it look worse than it is. My local ski tuner said when it's running rich it can run a little rough as well.
:bananalama:

 

[stanton]

doesnt sound like its running very good?

 

[Waternut]

It does look like the motor mounts are moving but coud just be the video quality. I find it hard to believe the engine could shake as bad as the video shows if all the bolts are tight. The being said...engine shake the worst, right off idle. If you rev it to 2-3k rpms, the engine should be fairly solid.

I agree with stanton... the engine doesn't sound very good though.

 

[adamrs80]

The rubber mounts are moving with the engine but the bolts are torqued to factory specs w/red loctite.

I don't think it's running real good. I just switched from a 95 gram spring to an 80 gram spring and have not messed with the low end much. I think my idle was too low as well. It was around 1300 out of water and I think it's supposed to be about 1600 or so in water. I raised it to 2000 rpm out of water and it smoothed out some. Do my carb specs seem way off? I think I'm probably rich on the low end.

 

[QuickMick]

HAHAHA welcome to the wonderful world of DRY PIPE shake.
My 61X with that same riva dry pipe shakes all the hell at low throttle.
Its that pipe.

 

[adamrs80]

Thanks Mick. Glad to hear the pipe is the culprit. When I'm working on the ski I kind of hate this pipe because it's in the way, but it sure rips when it's tuned right, hopefully I can get some time in the water tomorrow to get the low end right

So did you get elected? I was in Galveston last week at the Hotel Galvez for a wedding, the town is really coming back to life.

 

[QuickMick]

Thanks Mick. Glad to hear the pipe is the culprit. When I'm working on the ski I kind of hate this pipe because it's in the way, but it sure rips when it's tuned right, hopefully I can get some time in the water tomorrow to get the low end right

So did you get elected? I was in Galveston last week at the Hotel Galvez for a wedding, the town is really coming back to life.

My pipe is a love and hate situation. It is great in the surf, nail the throttle right before the wave, ramp up that thing and brap.
on the lake trying to get down the creek the pipe keeps ripping my arms off when it kicks in when trying to cruse.
I have the same cone FA on my motor and im on my second one. The first one ripped at the clamp.

 

[#ZERO]

Have you checked your cylinder compression lately?

 

[SJ Thumpa]

Where was the water coming from between the flywheel cover and the tank?

 

[adamrs80]

Have you checked your cylinder compression lately?

Yes it's 185 in both cylinders, checked it with a Snap-on compression gauge last week. I'm running 93 octane with Maxima octane booster.

 

[adamrs80]

Where was the water coming from between the flywheel cover and the tank?

Thats water that was left over from me washing the hull out. It's just standing water, not leaking from anywhere. Probably just splashing around. To little for the bilge pump to pick it up.

 

[Ericfox]

go to the lake and make sure your jets and popoff are right and adjust high and low adjusters... that might make it run smoother... did you align the engine without the rubber piece between the couplers like you're supposed to? Did you make sure it was as good as you could get it in all directions?

 

[adamrs80]

I did not align without the rubber coupler damper. I did use a straightedge and a tiny ruler to measure the space between the couplers. I also took the plugs out and rotated the couplers back and fourth with my hand and fingers between the coupler pieces to see if it's pinching or squeezing which would indicate that the couplers were not on the same line or level. How do you do it without the damper? Wouldn't you have to pull the engine back in order to put the damper back in?

 

[Dustin Mustangs]

Next is the engine. Slide the engine into place WITHOUT the rubber damper. The first stage here is to try to get the engine height figured out. Left and right alignment is negligible at this point. You want to add shims accordingly to each mount so that you can take a card and place it on the top of both couplers and have that card sit even.

Once you have that figured out, remember or mark the position of the shims, pull the engine forward, slide in the rubber damper, add your shims back, and just barely snug each engine mount bolt. You'll now twist the engine so that when you place a card on the sides of the couplers, the card will sit flush on both sides. You can also use a variety of measuring tools to determine whether each side is aligned properly instead of a card. Between each movement remember to snug atleast one bolt back down before you let go of the engine, otherwise you'll just loose the amount you have moved the engine. Once left and right alignment has been figured out, torque down all your bolts.

http://www.x-h2o.com/threads/51928