Rack re-assembly............

Okay so I took my whole carb rack apart (Hitachi HSC32's off a 1982 650 Maxim) to make sure everything is 100% clean and correct and detailed and now I'm in the final stages of being "all of the king's soldiers and all of the king's men"---and putting it all back together again.......

The only "problem" that I am (possibly) encountering has to do with the throttle shaft return springs.

My question is: how "tightly wound" should they be when initially installed?

I have another spare (complete, assembled) set of carbs here, and in looking at them, the return springs seem to be in an almost "coil bind" position with the throttles closed, so that there seems as though there would be quite a bit of closing tension on the throttle valves.

When installing the springs onto the throttle shafts, I have put just a little bit of tension on the springs.....just enough to get their end hooks onto the peg on the carb body, and into their slots on the lever arms.....and it's visibly different from the assembled carb as to how "tight" the springs are.

Although there is enough tension to close the throttle valves from their open position. I just want to make sure I'm doing this task right before I button this rack back together again!

Anyone know what I'm talking about, and have the answer? Thanks!

 

If you have a set there already, I would go by the feel of the spring tension in that set and compare it to your newly assembled set. You will know when you start to get close. Just open by hand to get a feel of the tension that is there.

 

Hey Fraps, thanks. The problem is that the other rack is assembled and I don't really want to tear it apart just to check spring tension (although it may come down to that......).

When I first assembled carbs #1, 2, and 4....which are the ones that use the smaller spring....it just feels like there barely any spring tension closing the butterflys. There's only one way to install the springs, so it's not a question of putting them on incorrectly, and because of the position of the mounting tangs, it's either "very little tension" or one full spin of the shaft around, which results in ALOT of tension (but they sure do snap shut quickly!). It just seems odd. Of couse, neither the Haynes nor the factory Yammy manny gives any guidance......

 

No - don't tear it apart. Actuate all 4 at the same time. This will take a decent amount of finger pressure to do. Do it a few times to get a feel for how much pressure it takes. Then...go to your newly assembled set and do the same thing - the pressure should be the same.

I know it is a bit of messing around taking the carbs off the rack to check the springs but you want to make sure you get it right.

Good luck!

 

I know this is an old thread - but what was the end result? I have my carbs in pieces in my kitchen right now have the same problem! I'm either going to have to have the springs somewhat loose or super-tight!

 

Okay. For future reference I'll tack this on. I re-built the carbs without winding the return springs tight. They were quite loose, but once the butterfly valves are in place and all the springs are working together everything seems right.