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Discussion Starter #41
Phil, just a little expansion on the technical explanation for the non-mechanically inclined, on what the vacuum hose to the petcock really does.

The middle vacuum hose does not suck gas into the carbs, but "sucks" or applies vacuum to a rubber diaphram which opens a valve and allows gas to flow by gravity through the two outer petcock hoses into the carb float chambers.:)

In other words, in a properly operating petcock no fuel passes through the vacuum hose.:smiley_th
Well said!!! :smiley_th
 

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OK, ordering the parts today. Hopefully after the earshave and a carb sync, my popping will go away.

Thanks again for this awesome blog.
 

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yanked everything off my bike, and I was able to get the surge tank out in less than 10 minutes. Using a saws-all, and coming in from the right side of the bike, cut from the bottom up just at the corner of the 90 degree "L"...cut through into the open oval where the air filter ducts were. Then continue cutting upwards at the top right corner of the open oval (be careful to NOT hit the frame of the bike as you will be close at this point). You just need to cut enough to where the 90 degree "L" can flex. At this point grab the surge tank at the base end and pull it straight out. Mine came out with minimal effort as the "L" shape was able to easily flex and come out.
 

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Clint '89
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Phil, just a little expansion on the technical explanation for the non-mechanically inclined, on what the vacuum hose to the petcock really does.

The middle vacuum hose does not suck gas into the carbs, but "sucks" or applies vacuum to a rubber diaphram which opens a valve and allows gas to flow by gravity through the two outer petcock hoses into the carb float chambers.:)

In other words, in a properly operating petcock no fuel passes through the vacuum hose.:smiley_th
Any clarification on why you chose the replacement sizes you did? Reading the manuals on carburator tuning, information from the other end might help to wrap up my knowledge of the subject, helping me to be more confident on the procedure.
 

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I did the earshave this morning.

First off. Thanks Voip Doc for posting this excellent tutorial. I would have been too afraid to try this without some detailed instructions. They were great and things went almost perfectly.

Only weird thing is my carb vent hose was actually attached to a plastic nipple on the underside of the fuel tank. Anyone know why or what that nipple is for? I re-routed it to an Emgo crankcase filter on the right side because I bought it anyway so I figured might as well use it.

Oh yeah, and there was a hose that came down from the bottom front right of the surge tank, ran behind the radiator, and just exited in front of the starter. Looked like a vent hose, but I thought the surge tank only sucked air, and I am confused about this line. I couldn't really find mention to it anywhere, and since it no longer had anywhere to attach on either end I just took it off

Also, I just wanted to add my 2 cents about cutting the surge tank. I used Cutco scissors. For those of you who don't know what Cutco is, they make a gimmicky high end knife line. They are actually quite good, but the I only have them because years ago I got suckered into the multi level marketing "scam" and had to buy a set in order to sell them. Anyway, the scissors are great, took 5 minutes to cut the surge tank out. See picture below to see where I made my 2 cuts.

Furthermore, I used a rubber stopper in the crankcase breather tube and drilled a 5/16 hole in it. I stuck the Emgo filter in there and clamped it all down. I simply didn't have any 3/8 fuel line handy so this was what I was able to whip up. Seemes to work well, but am a little concerned about a limited air flow here. Any input?

And Finally...


After I got everything buttoned back up, about 3 hours (I had done the coasters a few months ago saving me some time here) the bike ran great, and best of all....
..
..
..
..
NO MORE POPPING!!!!!

I have tried everything under the sun to get rid of my popping including replacing my entire exhaust with brand new V&H pipes, re-coastering, adjusting air mix screws to every possible setting etc...

I highly recommend this procedure to everyone. This is the best MOD i have done yet.

Thanks a bunch
 

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Clint '89
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I'm refibishing my tank and fenders today or starting- I forgot to buy bondo and remembered mention of the fuelline. How many clamps are needed and of what size, since I have to go to the auto store by bicycle It would be great to get this done in one shot(as much fun as it is for me to think of fuel in a biomechanics way).

2 k&N sized clamps, and some 3/4 th clamps? Rest of my ear shave stuff will come in on monday or tuesday, My handle bars will be all back togeather then so I can risk the fines to go out again, after my inspection.
 

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I'm refibishing my tank and fenders today or starting- I forgot to buy bondo and remembered mention of the fuelline. How many clamps are needed and of what size, since I have to go to the auto store by bicycle It would be great to get this done in one shot(as much fun as it is for me to think of fuel in a biomechanics way).

2 k&N sized clamps, and some 3/4 th clamps? Rest of my ear shave stuff will come in on monday or tuesday, My handle bars will be all back togeather then so I can risk the fines to go out again, after my inspection.
I'm confused. You should receive clamps with the K&N filters. The Emgo also come with clamps. You can used the supplied clamp for the carb breather tube. But you will need to get one a size larger than they come with for the crankcase breather tube. I think they come with either 3/8 or 1/2 so I suppose a 3/4 would be good here. Also when you say fuel lines I assume you mean for the emgo filters, because your fuel line to the petcock should already have clamps.

I hope this helps.
 

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Discussion Starter #50
I did the earshave this morning.

First off. Thanks Voip Doc for posting this excellent tutorial. I would have been too afraid to try this without some detailed instructions. They were great and things went almost perfectly.

Only weird thing is my carb vent hose was actually attached to a plastic nipple on the underside of the fuel tank. Anyone know why or what that nipple is for? I re-routed it to an Emgo crankcase filter on the right side because I bought it anyway so I figured might as well use it.

Oh yeah, and there was a hose that came down from the bottom front right of the surge tank, ran behind the radiator, and just exited in front of the starter. Looked like a vent hose, but I thought the surge tank only sucked air, and I am confused about this line. I couldn't really find mention to it anywhere, and since it no longer had anywhere to attach on either end I just took it off

Also, I just wanted to add my 2 cents about cutting the surge tank. I used Cutco scissors. For those of you who don't know what Cutco is, they make a gimmicky high end knife line. They are actually quite good, but the I only have them because years ago I got suckered into the multi level marketing "scam" and had to buy a set in order to sell them. Anyway, the scissors are great, took 5 minutes to cut the surge tank out. See picture below to see where I made my 2 cuts.

Furthermore, I used a rubber stopper in the crankcase breather tube and drilled a 5/16 hole in it. I stuck the Emgo filter in there and clamped it all down. I simply didn't have any 3/8 fuel line handy so this was what I was able to whip up. Seemes to work well, but am a little concerned about a limited air flow here. Any input?

And Finally...


After I got everything buttoned back up, about 3 hours (I had done the coasters a few months ago saving me some time here) the bike ran great, and best of all....
..
..
..
..
NO MORE POPPING!!!!!

I have tried everything under the sun to get rid of my popping including replacing my entire exhaust with brand new V&H pipes, re-coastering, adjusting air mix screws to every possible setting etc...

I highly recommend this procedure to everyone. This is the best MOD i have done yet.

Thanks a bunch
Congrats! :smiley_th
 

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Patriot Guard Rider
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Ordered the earshave parts on Thursday and expect to shave her next weekend. Thanks for detailed parts list and where to get them.
 

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Hi everyone. I'm going to order the parts that I need to do my ear shave tonight. My question is, are the size 142 jets just for the ear shave? I plan on putting an exhaust system on my bike as well (probably Vance & Hines) and want to install big enough jets for the shave and the exhaust at one time. Thanks. :confused:
 

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Discussion Starter #53
Hi everyone. I'm going to order the parts that I need to do my ear shave tonight. My question is, are the size 142 jets just for the ear shave? I plan on putting an exhaust system on my bike as well (probably Vance & Hines) and want to install big enough jets for the shave and the exhaust at one time. Thanks. :confused:
Depends where you live...altitude!
 

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I'm in Pennsylvania, a few miles north of Gettysburg. I do most of my biking locally and don't have any plans to do any high altitude riding. The bike in stock form runs perfectly right now at this elevation. Google says that I'm about 500' above sea level.
 

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Discussion Starter #55
I'm in Pennsylvania, a few miles north of Gettysburg. I do most of my biking locally and don't have any plans to do any high altitude riding. The bike in stock form runs perfectly right now at this elevation. Google says that I'm about 500' above sea level.
'bout the same here...
140 mains / 40 pilots or 142 mains / 42 pilots...either should work fine.
I chose the 142/42. I have V&H Cruzers, but it didn't factor into decision.
You may want to start mixture screws at 2 turns...then after new pipes, back out another half turn....tweak after running awhile
 

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Post ear shave help

Okay, I got all my parts for the ear shave and did the procedure last night. I put in 42's and 142's. Assembly went well and I did the rectifier relocate as well. My problem is that now my bike went from being one of the easiest to start bikes I've ever owned to the hardest to start bike I've ever owned. When she does start, she idles fine but stalls if I goose the throttle (will rev up if I'm gentle). I've played with the air fuel screw from 1.5 turns out to 3 turns without improving starting and the throttle hesitation problem. I've put about 10 miles on it and she seems to drive fine and I can feel the additional power. I've been messing around with the carbs for a couple hours now and starting to wish that I hadn't done the shave at all. Any suggestions? .:confused::confused::confused:
 

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If only it had 6th gear..
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I was sent the wrong pilot jets when I did mine. The heads were short (looked more like the main jets) and mine would idle but as soon as I gave it some juice it stalled unless I eased it up in the revs. Now, it was pretty much not ride-able with those jets so since you've put some miles on it, it may be something different. Did you plug your vacuum nipple on the right hand carb? And the hose that wwent to the right side ear, is it unblocked. I think a substantial vacuum leak could cause what you're describing as well. Needle diaphragms in good shape and seated well? The more detail you give on the procedure, the better and quicker you'll get an answer I bet. Hope it's a simple fix.

Don't be bummed out tho. Mine still isn't running because I have a float problem now but when I blasted it down the street before flooding the ^*&* out of it, I was very happy with the improved acceleration. You'll get it running right soon.
 

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I followed VoIP DOC's procedure to the "T". Maybe there is a vacuum leak. I'll try the WD-40 trick around the boots. I did check the jets before I installed them. The numbers were correct and they looked exactly like the OEM's. The right carb does have the vacuum nipple plugged and i replaced every hose with fresh lines while I was in there. I haven't replaced my exhaust "yet", but I did drill a few holes around the baffle plate (two years ago). I just tried to start it again and I had a backfire from my exhaust that sounded like a 12 gauge shot gun.
 

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Discussion Starter #60
I followed VoIP DOC's procedure to the "T". Maybe there is a vacuum leak. I'll try the WD-40 trick around the boots. I did check the jets before I installed them. The numbers were correct and they looked exactly like the OEM's. The right carb does have the vacuum nipple plugged and i replaced every hose with fresh lines while I was in there. I haven't replaced my exhaust "yet", but I did drill a few holes around the baffle plate (two years ago). I just tried to start it again and I had a backfire from my exhaust that sounded like a 12 gauge shot gun.
Are you sure the carbs are seating properly on the cylinder boots?
Are you sure the diaphragms were seating properly before tightening the covers?
Unburnt fuel in exhaust is causing the backfire on startup...Sounds like it's flooding to me.
Don't give up.
 
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