There is an error in the AC 2000 service manual regarding the valve clearances on the 400 and 500 cats. In section 2- Service and Maintenance it reviews the valve adjustment procedure and shows exhaust clearance as .009-.011. In section 3 under engine specs it states that the exhaust clearance should be .007-.009. I spoke with AC and they confirmed it is .007-.009. I,of course, noticed this the morning after doing the valve adjustment. The interesting thing is that the exhaust valves were close to .012 so I adjusted them to .010. It seems that they left the factory adjusted at .009-.011. If not, they were along way out for 700 miles. I am hoping that this may provide a little more snap, as the engine should breathe a little better. I remember someone else had done some valve adjustments and just thouhgt you guys should know.

Cheers Jim

 

Thanks for the tip Jim! How many miles do you have now? I've put on about 760 or so, and will probably add up another 50 or so this next weekend, but that's just a guess. Is there anything I should do, or check at that amount of mileage? Been changing oil every 300, cleaning air filter regularly, but that's about it.

Boner, didn't you do something with your valves a while back, or was that Andy? Was it because it needed it, or just out of curiousity?

Thanks for the tip!

Mike

 

That was me. It said to do it at 1600 miles and I tired it at like 2400 miles. I ended up doing more harm than help cause I adjusted the exhast valves to tight and had to go back and redo it.

Later I talked to the mechainic and he said he as seen bikes go 5000 miles and them never touch the valves so will leave mine alone till it NEEDs to be adjusted.

 

I had 725 miles on the bike. The dealer tells me he never checks the valve clearance. But when I called him and told him that the exhaust valves were close to .012, he said to adjust them for sure. Cowboy, on another note, I remember not so long ago that you had added some spacers to your shocks. Can you provide a pic or some details, I would like to get my front end up a little, but do not wish to add a lift kit. Your idea sounds like the best solution.

Cheers Jim

 

Boner, were your valves out of adjustment. Also I would be curious as to what your mechanic would do with the clearance I had on the exhaust, .012. Your post makes me a little nervous, although I am following the maintenace schedule to the letter.
Cheers Jim

 

All I remeber is that they were tighter than they were suposed to be so I just adjusted them, I didn't check to see how far out they were.

Since they get tighter as they wear I decided to set it at the maximum looseness--.009 for the exhast(I think) and .003-4 for the intake(I think).

 

Thanks Boner, and Jim for the advice, I'll just leave it alone for now, wait till later on down the road.

Jim:
Do you carry much weight up front? I do, as you know by now, and for my needs, the 3/8" spacers worked the best. I feel the 1/2" were way to stiff, and since there was no increase in clearance in going from the 3/8" to the 1/2", it was just not worth the ride.

If you are looking into it, I'd recommend getting your local steel shop to cut you the two spacers you'll need for the front out of either aluminum or steel pipe. The steel shop here was closed when I did mine, so I had to use 7/8" shaft collars and cut them to size. I believe the inside diameter is about 1 1/4" or so, if I remember right. It is just big enough to fit around the head of the shock, and slide down the cylinder. The wall thickness is roughly 1/4". I wouldn't go much narrower than this, as this is what provides your new "base" for the spring to rest on (on top of the stock washer anyway).

First, you'll need to elevate your machine, with both front tires off the ground-or at least the one you'll be working on. You can remove the tire, but it's not necessary-I left mine on every time I swapped them in or out, and it worked fine. Just have to feel for the bottom bolt/nut.

With the tire off the ground, remove the shock from the machine, by removing the upper and lower bolts. I don't know that order matters, but I've always removed the top first, then the bottom, and actually found it easier to install the bottom first, then the top upon finishing.

Once the shock is off, you'll need to compress the spring a bit, to remove the top spring retainer. If you have a spring compressor handy, that works the best-easiest. I used pure arm strength, and this proved to be a little tough with the 1/2" spacers. You should be fine with the 3/8" though, if you have somebody to help remove the retainer, while you are compressing the spring.

With the retainer out, slide the spring off, then the plastic spacer between the spring and the shock, then the bottom base plate that the spring rests on. Now, slide your new 3/8" spacer back on the shaft. This is your new platform. Then, slide the base plate washer back on, followed by the plastic spacer, then the spring, and finally compress the spring and install the top retainer. You won't see any difference in the actual length of the spring/shock, though when installed back on the machine, you've essentially "stiffened" the spring, which makes the machine set higher, giving more ground clearance or the ability to handle loads better.

I gained 1 1/2" of clearance by adding the 3/8" spacer to my machine. You may be able to get a little more lift out of an actual lift kit, though from what I've seen of the angles, I think the lift kits put the cv joints at a steeper angle, and thus cause more wear than the spacers do, but that's just my own theory. If after trying the 3/8", and find it to be too stiff for your liking, you might want to shave it down a bit, to 1/4" or so and see how that works.

I'll try to post some pics of it, though it will be a while as my newest disposable only has a few pics taken. I've almost lost my faith in the developing place, as they've completely lost my last roll of all my elk hunting, and driving in mud, up hills with only 3 wheels on the ground. I'm pretty pissed about that one, as I also had one I thought you guys might get a kick out of. Last day of elk hunting, our meat poll was empty, so I decided it would be cool to hang my 'Cat. I hooked up the winch cable, and hung my 'Cat from the meat poll, at which time the entire group got together for a picture. It was pretty cool, and kind of fun as well. I was hoping to get them posted for you all to see, but it seems they've been mis-placed by the developing company. Who knows if I'll ever see them.

Oh, and I can't take credit for the idea behind the spacers. Trailboss suggested I try it out, and I'm sure glad he did. For my needs, they've worked excellent, so the thanks go to him for the idea.

Best of luck, and if you need any other information, don't hesitate to ask!

Mike