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Need To Source Carb Vacuum Ports

12 posts Started 24 May 2013 Last recovered post 2 Aug 2016 Wayback Machine snapshot 10 Jul 2017

#1

The last time I wanted to sync my carbs was about 9 months ago, but I never started because I have screws blocking my vacuum ports. I need nipples (and who doesn't?), but I don't know where to find them. I've balanced carbs before on my FZR and my brothers 900SS, but this is the first time I've had to source the nipples.

Is there any reason to not leave the nips in place and cover them with a rubber boot?

Please let me know where I need to beg/borrow/steal/or heaven forbid buy these from.

#2

On your GEN 3, the screws come out and the hose nipples are screwed in to attach whatever sync device you are using. On the GEN 4s, the nipples are brass and already in the carb body. I just leave the little rubber boots on 'em 'til the next time I need to sync the carbs. I can highly recommend the Morgan Carb-Tune from the UK, works great. Good Luck!

#3

I just can't seem to find the nipples online. I don't want to go the dealership and pay 7.95 for something I can get somewhere else for 75 cents. Does someone have a diameter and pitch?

#4

I had the same problem with my 93, it had the screws in it and I had to take them out each time I synced the carbs. I just ordered all the stuff off of Bike Bandit for a 1994 for a heck of a lot cheaper and it fit right in. I haven't had any issues since.

#5

Cant you take the screws out and measure them, or at least take it to a hardware store and use the thread checkers there?

#6

Oh, sure, Yoshi. Come up with a total viable alternative. :goofy: Of course I could, but I was hoping to order them ahead of time, and then I can sit down and do eveything at once. I thought they would be easier to source. I was certain someone here would know where to get them. I'm going to try Sudco real quick, but if that doesn't pan out that may be what I'll do. I'll check Bike Bandit too.

#7

Great thought. I'm using a DIY. I just have to find out what size to get. Sudco was a bust, but they told me to try Motionpro. MP has two sizes, 5mm x .8 pitch, and 6mm x 1.0 pitch, both at $4.50 a piece with a little gasket and rubber boot. I think it maybe time to listen to Yoshi, I'll be pissed if I spend $30 for the wrong size.

Maybe I'll try a hobbie shop.

#8

Rubber caps degrade over time. I think the coloured vinyl caps last longer. M5 is the thread, IIRC.

Ciao,

#9

Thanks all. Parts are ordered. Those that follow me will thank you.

#10

Hoses on vacuum ports? On my 1993 VFR750F, the two front carbs (#2 & #4) have hoses attached to the only things that resemble the vacuum plugs on the rear carbs.  The hose from #2 goes to the water pump; the one from #4 goes to the coolant overflow tank.  Are these the ports I should use?

#11
1 hour ago, SAW

Hoses on vacuum ports? On my 1993 VFR750F, the two front carbs (#2 & #4) have hoses attached to the only things that resemble the vacuum plugs on the rear carbs.  The hose from #2 goes to the water pump; the one from #4 goes to the coolant overflow tank.  Are these the ports I should use?

I think you are following the hoses incorrectly. As you are in the US, you most likely have the air injection system. This is tied into the front two carbs but in no way connects to the cooling system.

#12

Thanks, Coupedupsubie.  That makes more sense.  I must have followed the hoses wrong; lots of stuff crowded into that small space.

End of thread · 12 posts recovered Wayback Machine snapshot 10 Jul 2017