TOPIC:

Using Harbor Freight gauges. Could you just get 4 of these? With coupons you can get them for $10-12 each.
Would ou need anything else to go with them?

Very nice, not sure why there are 6. It may need vacuum restrictor to build up pressure. dorman part #47311 may work.

I found this picture on a Valkyrie site.

might want to try one first to see how well it functions on one carb. I have one and tried it and it went nuts, but it wasn't running well due to mechanical difficulties.

I used a clear plastic hosw about 6 feet long, tied it to a yard stick and filled it with oil. I had to balance the fluid before I could use it but it works good for the twin cylinders.

No eBay APP ID and/or Cert ID defined in Kunena configurationNo eBay APP ID and/or Cert ID defined in Kunena configurationHi Flyndrive,
If the gauges are decent it should work as long as you set up plumbing correctly. You will want a super tiny restrictor (pilot jets may work, but adjustable needle valves would likely be better). The hole needs to be as small as possible, and should be clean, and the material must be ridgid (plastic is problematic).

The restrictor should be as close to the engine-end of the tubing as possible. This will make the needles less jumpy, and will prevent the tubing from affecting the manifold vacuum.

Get a 4-into-1 manifold so you can calibrate the gauges to one cylinder so they all read the same.





On a 550, you want the vacuum to be all within about 5mm of mercury of each other. That's like 1/4" of mercury. So make sure the gauges will let you see 1/8" mercury differences easily.

Way more details are available here about restrictors etc. They are written for mercury, but the part about restrictors applies to any gauges:
home.comcast.net/~loudgpz/GPZweb/Manomet.../ManometerNotes.html