When your doing the Airbox mod, do you also disconnect and plug up the KCA Air Suction System? If so do you plug up both the airbox port and the Air Suction Valve? or do you put a breather filter on the Air Suction Valve and just plug up the air box port?

Any insight would be great, thanks,

Dave

 

I pulled that sucker off right away. To do so, I suggest you plug the vacuum port on the carb that drives the valve, the hole in the airbox that provides air to the valve, and the reed valve inlet on the front left side of the head that allows the air to enter the exhaust stream. You could put a breather on the valve but why? Getting that system off the bike completely does nothing but good. It greatly reduces exhaust head pipe temps (and I believe exhaust valve temps) and removes an opportunity for a vacuum leak down the road.

 

Has anyone come-up with a better solution than Help brand plugs and caps?

 

thats what im wondering... those things crack... thats y that system is still on my bike... im thinking of just cutting the hoses off short and getting a bolt to fit in the end of the hose and use a hose clamp to hold it in there and use the bolt as a plug... that wont crack or dry rot or whatever.... any thaughts on this?

 

I used the plugs on the carb and air box but made an aluminum plate for the front of the motor. So far so good.

 

Sounds like it might hold-up better. I was actually thinking of the same thing.

I also remember an old mechanic's trick of pushing an appropriate sized steel ball bearing into vacuum hose. The trick was to find a ball bearing that fit tightly into the hose and would also be too large to get sucked into the nipple. This would, of course, require the hoses to be left in place, which is not desirable for most of us here. I was just looking for an interim solution until something better than the Help plugs can be found.

 

I cut the reed valve inlet hose off to 2" and capped that with a hose plug. 2" seems to be enough to keep the heat of the head from melting the plug.

 

Good idea. I'll probably go that route.