TOPIC:

I have a 1982 Spectre 750 all stock. It runs great after cleaning it up/tune. I took it on a 200 mile trip the other day. I was looking it over today and I noticed a small amount of oil leaking from the air suction valve covers. Could my gasket simply need replacement or is this indicative of a more serious problem? I'm going to inspect the reed valves tomorrow and make sure everything looks okay in there. I can post pictures if anyone is unclear what I'm talking about.

Thanks!

Go to www.aperaceparts.com and see if they make a block off plate for your bike. Most riders remove the "Smog Gear"(the vacuum lines, reed valves,and the air switch) capping off the open lines.Run a hose between the two covers at the exhaust reed valve area.

Most auto parts stores sell a selection of rubber hose caps that should fit the vacuum lines.

This sytem was designed and built by Kawasaki to reduce exhaust emissions. The official name is the Kawasaki Clean Air Suction System(KCASS). It neither adds nor subtracts horsepower from the engine.

Sounds good to me.

I found the parts I need. About to order now....

Thanks, MFolks!!

Run a hose between the two covers at the exhaust reed valve area.



if your looking for a plate to cover these with...how do you run a hose from one reed valve to the other? and why??

I believe ape race parts has block off plates, if no luck, you can make your own with a thin piece of Aluminum, using the redd valve cover as a template. The hose between the two covers will balace out any pressure/vacuum.

im sorry, i still dont understand. your blocking the whole thing off, yet putting a hose between the two covers? i seen them on ape, and theres no where to put a hose on them

nitrokrumpt wrote: im sorry, i still dont understand. your blocking the whole thing off, yet putting a hose between the two covers? i seen them on ape, and theres no where to put a hose on them

You misunderstand. You can cross connect them with a hose OR use block off plates. The plates are a cleaner look. The system is actually beneficial because it helps evacuate the crank case. It looks rather untidy though.

You should't see oil seeping from the system anywhere. If there is, it's possible the engine oil level is too high and oil is being forced up into the airbox where it's being drawn into the engine. Also possible there is a lot of compression blow by pressurizing the crank case and forcing some oil up.

When the air injection paraphernalia is removed, the basic idea is to prevent outside air from being drawn in through the ports protruding from the stock covers.

Options include --
• plugging each of the two ports;
• connecting the two ports;
• replacing the stock covers with aftermarket covers that don't have such ports;
• various other methods.

Good Fortune!

The system is actually beneficial because it helps evacuate the crank case. It looks rather untidy though.

ok what system is beneficial, having the vacuum or not?? and also, i have the petcock with the vacuum line to it, would that be taken out the equation as well if the vacuum system was deleted? gas flow wont change???appreciate it you guys. and ultimately, whats the best way to run this bike... i would like to delete the damn vacuum for i am chasing a vacuum leak for the last 2 weeks

nitrokrumpt wrote: The system is actually beneficial because it helps evacuate the crank case. It looks rather untidy though.

ok what system is beneficial, having the vacuum or not?? and also, i have the petcock with the vacuum line to it, would that be taken out the equation as well if the vacuum system was deleted? gas flow wont change???appreciate it you guys. and ultimately, whats the best way to run this bike... i would like to delete the damn vacuum for i am chasing a vacuum leak for the last 2 weeks

You need the vacuum like for the petcock. You don't need the vacuum lines going to cylinders 1 & 4 if you intend to remove the clean air system. You can cap the manifold fittings or cross connect them with a length of the vacuum hose from the system.

If you keep the system in place, you need the vacuum line running to the air cut valve in the clean air system. It's purpose is to shut the valve during periods of high vacuum in order to prevent back firing in the exhaust system.

For decades, car guys have been fabricating crank case scavenge systems that connect to their headers in order to reduce internal crankcase pressures.

If you eliminate the air box and go with individual filters, you may as well remove the clean air system as it will be rather noisy without the sound deadening properties of the air box attached. You can simply pull the hose out of the air box and fire up the motor. You'll hear what I'm talking about.

It's not a major performance boost by any means. It's one of those little bit here, little bit there scenarios. Racers are always looking for free power In heavily modified engines it can be beneficial to have additional help reducing crankcase pressure. After all the piston has to fight against internal pressure on the down strokes.

Yamaha actually drilled out passages in the crankcases on the FJ1100 so that gases in the crankcase being displaced by the falling pistons could travel to the 2 other pistons and assist, every so slightly in pushing them upward. Again....if it's free...use it to your advantage scenario.

Back in the 50's I think it was Chrysler that first figure out that if you introduce fresh air directly into the exhaust port right near the valve guide, it can burn unburned gasses that are frequently present in the exhaust gases. As emissions got tighter, Kawasaki simply used the same principal on their bikes. It first showed up in 1979.

IF you over fill your engine oil, it can get forced up into the airbox where it can be ingested by the carburetors and also the clean air system.

explained very well thank you crh. now can you get rid of the clean air system, and leave the airbox alone. i dont mind the airbox i dont think, other than the 3 times i had to take it apart and put back together being a pain in a rear, but i can handle it