Building Manometer for barbless carbs: Where do I get a threaded nipple???

[cmattina1]

So, I have carbs without vacuum barbs on the carb holders. From reading the carb guide I see that,

"Also note the vacuum ports available on the 38s (arrows). A suitable threaded nipple can be installed in place of the block-off screw to enable gauge hook-up for syncing. This is only necessary if you have no vacuum barbs on your intake manifolds ('77 and older). The size is a standard M6 x 1.00 ....."

Am I able to simply buy a threaded nipple (M6 x 1.00)from a hardware store or is there a particular one I can buy, i did not see anything on xs650direct.com

 

[DogBunny]

http://www.650central.com/carb.htm
A bit spendy.

http://www.universalcycles.com/shopping/product_details.php?id=191
These are a whole lot cheaper. Scroll down to item# 191-28148. I bought these, the threads are a little long, but they work for me. Or, you can trim the threads a little if you need to.

And no, you can't get these at a hardware store, they are a bitch to find.

 

[5twins]

I guess some use an M6 grease nipple with the ball and spring removed.

 

[blackbetty]

I use these on my 76-77 BS38's, they kick ass.

http://www.motionpro.com/motorcycle...ns&utm_medium=affiliate&utm_campaign=webgains

 

[DogBunny]

The grease nipple is a great idea, wish I'd heard of it sooner.

 

[ember]

I ended up using a regular 6mm x 1.0mm allen head bolt which I drilled a small hole down through the center on my lathe. Turned down the heads of the bolts on a sander to fit the tubing. Worked for me. But the motion pro adapters listed above would have been awesome. Just didn't want to pay extra for shipping.

I used Marvel Mystery oil in my monometer. Have your finger on the kill switch until you can get them synced closely. When I fired mine up and took it off choke for the first time, it sucked hard from the right side carb.

 

[cmattina1]

Yeah, I attempted yesterday and sucked some ATF into the left cylinder. It was a bit of a shitshow, as I wasn't sure how good of a seal the tubing had on the nipples resto sent me. So there I was squeazing each nipple, being weary of the kill switch, and trying to adjust the screw.... I put out an ad to borrow one last night and had a few hits. surprising thing is, they were apparent way out of sync, but I went for a ride around the block, and it ran fine....

 

[retiredgentleman]

I've mentioned this a few times in the past.

If you don't know how far out of sync the carbs are, its best to remove the carbs from the engine to the bench. On the bench use a piece of paper as a feeler gauge, and adjust the sync screw for equal drag under each butterfly.

That will have the sync so close that there is no possibility of sucking fluid into the engine.

 

[strang]

I just found some after a long search by typing "hose connector m6" into ebay. came up with some good cheap brass options.
Stay away from anything that refers to "bsp" thread as my brother has just told me it's another world of thread sizes.