1975 bs38 choke question

[TC2000]

 

[TC2000]

It is the pipe with a surrounding spring

 

[Jim]

My xs1 has a pipe connecting both intake manifolds; I suppose it has to be blanked off in order to make any meaningful vacuum comparison

Correct. That balance tube was deleted on all subsequent years, so obviously it wasn't needed. If it were me I'd just install a capped barb on each intake and delete the balance tube.

 

[toglhot]

When I made my manifolds I, punched in a barb on each to connect a manometer, when the manometer is not connected I join the two barbs via a short length of hose, a la Bonnevilles.

 

[thatguy]

Hay guys thanks for the info. I got another question. My bike has spark 130psi cold for compression. And I am trying to use starting fluid. To start it with no luck... any sugestions?

 

[Bumblebee]

Ignition timing checked?
Cam timing is right?

 

[thatguy]

I'll check tomarrow

 

[grizld1]

Troubleshooting is a process of elimination, so do it all: cam timing inspection, cam chain tension, ignition service, and valve lash. Yamaha's book specs for compression are given assuming a warm engine turned at 200 rpm, which is about what the electric foot will do if it's healthy. 130 psi cold off the boot is pretty good.