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Discussion Starter #1
I previously replaced my carburetor intake boots (needlessly I might add), due to what I thought were cracks. They were surface cracks only. Anyway I replaced them with these From Amazon:

https://www.amazon.com/gp/product/B07143Y4HK/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

Be careful with the Amazon ones, the small vacuum connections on mine came loose and you can pull them completely out of the boots. Found that out while trying to sync. Cheap for sure. OEM next time. I replaced them back with the originals, and while putting them back on I accidentally placed them so that the screws to tighten the bands at the top were on the air box side. I guess I reversed the boots front to back. At this time I noticed that the carburetor sits more level with the bike in this position. I couldn't reach one of the top band screws to tighten due to the carburetor itself, so I switched it back- but I noticed once I mount the carburetor it appears to lean a little to the port (left) side.
My questions :
1) does the carburetor normally sit tilted to the left?
2) can this cause a float problem?

Thanks in advance!
 

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2009 650 classic white
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As many times as I have had the carbs off, you'd thing I'd know this. So someone correct me if I am wrong, but I think it does tilt a little to the left. Look at the boots coming out of the airbox, I believe they lean a little too.
It shouldn't tilt so much that it would affect the floats, doesn't hurt to check the float level anyway.
If you loosen the boot bolts can you move the boots a little to get them straighter? I have never had to take mine off ,so I don't know.
 

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Discussion Starter #3
I don't think you can move them much with the boot bolts, I think the bolt holes were pretty close.
Just seemed odd to me. I can make them straighter by reversing front to back, but I have a hard time getting to that band screw that tightens to the carburetor.
 

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I looked at the exploding drawing on bike bandit for the carbs:

https://www.bikebandit.com/oem-parts/2004-yamaha-v-star-classic-650-xvs65as/o/m145479#sch296696

The front and rear intake manifold boots are different part numbers.

The hose clamps that hold the carb bottom onto the tubes comes off, so if you left the original clamps on the original boots, they would have been pointed in the right direction if the boots were put in the right location.

If you had taken the clamps off and got the boots mixed up, all you had to do was spin the clamp around and unscrew it from itself, flip it over and put it back on. Easier typed than done - I know.

Since you have the original boots back on, if you can see the part number molded into the boots, you can tell if you have them in the right place, and go from there

but if you have everything fastened down and the air filter intake side is all connected and nothing is strained, I dont see a problem if the carbs are slightly tilted to one side. If the bike is running ok I would let it go till the next time you check the valve timing (another 12 to 16k miles maybe?) and then swap them back when you have the carbs off. To quote the first rule of motorcycle maintenance: If it aint broke, dont "Eff" with it.

The last time I had the carbs off my 650 for a valve setting check I did not notice that the carbs seemed to be tilted. I think I would have noticed it if they were, but cant be 100% sure. I had a hard time getting the clamps on the top side of the carbs back on to hold the airbox in place - took me three attempts to get the air box to stay seated while I tightened up both clamps - about 30 minutes.
 

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Discussion Starter #5
With the exploded parts diagram- it looks like the screw heads on the clamps should be on the starboard side. Mine are on the port side. I may have it reversed. The boots have a raised spot so the boot clamps have to go a certain way. I'll get out there and check everything again. I think I may have to pull the carbs again anyway, I've got hesitation or bogging from 1/4 to 1/2 throttle, idle is good and when I open it up it responds well. I got out on the road Sunday afternoon for a short distance (had throttle taped and marked) trying to see where problems are. I'm going to check some of the smaller passages, I've got the PMS screws out to 3.5 to get idle correct.
 

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Ride the bike a good 5 miles before you evaluate its performance, adjust the idle or balance the carbs.

My 650 is always a little boggy when the engine is cold in the morning - thats normal.

The recommended number of turns on the PMscrews is only the starting point for your bike setup, you normally have to tweak them a bit from there.

If you google adjusting the PMS there are two different ways to dial them in...
 
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Discussion Starter #7
Thanks. I always get the help I need here, and it is appreciated!
 

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Super Moderator "Loose Nut" - Houston, Texas
2001 Vstar 1100 Classic (sold), 2006 HD Electra Glide Ultra Classic
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Screw the PMS screws in until they are lightly seated...

The next part is up to you.......

A) if you think you can tune it by ear then run the screws out about 3 turns with stock screws, run the bike and see if you have popping on deceleration, if you do then turn them out in 1/8 increments until the popping goes away and you will be close enough. Re-sync the carbs after doing this.

B) PREFERRED METHOD - The Lean Drop - If you have a tach, start at 2-1/2 to 3 turns out equally on both carbs with stock screws and then gradually turn each screw in until the idle drops slightly. Then back them out slowly to the point the idle just comes back up. This is called a "lean drop".
 
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I looked at the exploding drawing on bike bandit for the carbs:

https://www.bikebandit.com/oem-parts/2004-yamaha-v-star-classic-650-xvs65as/o/m145479#sch296696

The front and rear intake manifold boots are different part numbers.

The hose clamps that hold the carb bottom onto the tubes comes off, so if you left the original clamps on the original boots, they would have been pointed in the right direction if the boots were put in the right location.

If you had taken the clamps off and got the boots mixed up, all you had to do was spin the clamp around and unscrew it from itself, flip it over and put it back on. Easier typed than done - I know.

Since you have the original boots back on, if you can see the part number molded into the boots, you can tell if you have them in the right place, and go from there

but if you have everything fastened down and the air filter intake side is all connected and nothing is strained, I dont see a problem if the carbs are slightly tilted to one side. If the bike is running ok I would let it go till the next time you check the valve timing (another 12 to 16k miles maybe?) and then swap them back when you have the carbs off. To quote the first rule of motorcycle maintenance: If it aint broke, dont "Eff" with it.

The last time I had the carbs off my 650 for a valve setting check I did not notice that the carbs seemed to be tilted. I think I would have noticed it if they were, but cant be 100% sure. I had a hard time getting the clamps on the top side of the carbs back on to hold the airbox in place - took me three attempts to get the air box to stay seated while I tightened up both clamps - about 30 minutes.
Is there a trip to connecting the top air box to the carbs because I have been trying all afternoon, I have to stop as it was so aggravating.
 

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The trick to the air box, is to loosen the clamps ALL the way, till the screw is about to fall out, then I usually spit on my finger and run it around the openings. Ease and wiggle them down over the carbs and check with a light to make sure they are on all the way before you tighten the clamps.
Also what Jspree said.
 

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I hated having to answer that way, but there really is no special trick, it is just too small an area to do anything, and you can't explain, you just have to play with it moving it around and it will just all the sudden just slip on. Sometimes it is quick sometimes is you want to take a big hammer to the whole thing.
 

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Super Moderator "Loose Nut" - Houston, Texas
2001 Vstar 1100 Classic (sold), 2006 HD Electra Glide Ultra Classic
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Or just have small hands like me. 🤭
There is no trick, but lubing them a bit as @skypupbob does help.
 
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I am glad that as a 650 owner I have long skinny fingers. . . . And that i can grab the top of "restaurant" food cans with either hand and flip them upside down while only holding the top with one hand.
😀

Lesblank beat me to the "I have small hands" post.
 

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The trick to the air box, is to loosen the clamps ALL the way, till the screw is about to fall out, then I usually spit on my finger and run it around the openings. Ease and wiggle them down over the carbs and check with a light to make sure they are on all the way before you tighten the clamps.
Also what Jspree said.
Thanks to everyone who helped me. I will get my finger and spit ready for my next try at this
 

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I struggled for a few minutes too my first time, then I used a little silicone spray inside the boot. A word of caution, that also makes it easy for the carbs to back out again!
 

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After loosening the band clamps all the way I used a heat gun on the rubber at a low temp to soften it up. Then put some 3 in 1 oil on the inner lip.
Then just wiggled it around until it slipped on. Same thing we do with all the rubber lines inside a coffee machine when repairing or rebuilding it.
 
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