Husqvarna cr500 '83 & up air cools

Now I'm seeing a difference in head nuts. The '83 cr500 seems to take the standard hex flanged nuts we all use.
I see the '83 being advertised for sale with these standard nuts. Now I see the '84 cr500 head nuts that appear to have a nut with a sleeve machined in that allows more thread for securing. These cylinders and head are advertised as '84? I'm gathering the cr500 air cooled ran from '82 to '84? I can't find the nuts with the sleeve anywhere. I haven't tried HVA FACTORY or HALLS yet. Are any of you cr500 guys aware of this?

http://www.ebay.com/itm/1984-HUSQVA...e410223&pid=100033&rk=5&rkt=8&sd=230836162465


http://www.ebay.com/itm/232234856142?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

Here's the two different cylinders?

1984 is different, the part # for the 84 cylinder head nut is 16 11 190 01, the part # for the washer that goes with the nut is 16 10 674 01. Don't know what the availability is.

Husky changed the head nuts to the type you described and shorter studs in 84 on the 500's. Also the head changed due to the stud holes were made larger to fit the new style of nuts. Husky did this so you could remove the cylinder while the motor was installed in the frame. The 83 500 studs are longer and you cannot remove the cylinder without removing the motor from the frame.

Marty

I have a cylinder and head off a 500 auto and as I recall examining the parts the way the head and cylinder fit together was different than the earlier parts I had to compare to.

Does post 3 above mean when I converted an 86xc 500 engine to air cooled I could have used the 84 top end including nuts instead of switching the studs and using the earlier top end?

I have taken the cylinder and head off at least one small water cooled two stroke bike as a unit to service the powervalve assembly where talk on the internet is it can not be done without breaking the head/cylinder apart.

Frank,
I have not tried that swap myself. But I am fairly certain the length of the 85-87 500 water cooled cylinder studs are different compared to the 84 500 air cooled cylinder studs. The part number for the water cooled studs is 1611883-03/1611883-04 and the 84 air cooled studs are 1611883-02

Marty

I have built 500 and 4t bottom ends specifically for multiple swaps.
M14 od m10 id 30mm long inserts are installed in the casings with capscrews replacing the studs.

I guess 82.5 & 83 years 2T use just the flanged nut while the 84 uses the sleeves and nuts. Right?

removing the cyl and head in one assembly is the go...I stupidly stripped the head of my 300 kato before pulling the barrel off and how hard do you think the flaming sealing "o" ring is to get on during reassembly nothing for it to hold on and it kept folding up like a rubber band on a propellor model plane

Yes, but be sure to use the correct length studs for each style of nut.

Marty

Since the 430cc & 500cc are similar in bore sizes does the 430 head fit the 500 cylinder in the first design with the flanged nut?

I use a 500 head on a 430 in the water cooled. Higher up in this thread I stated that the way the head fit onto the cylinder was different the one that came on the 500 auto vs the earlier one. It may be wrong but assuming I am correct you really need specify which 500 you are asking. I know I experimented mixing and matching at one time though do not recall. I think it would be possible to get the 500 (82.5-83) head on the air cooled 430 would have to go and experiment. Do not have the necessary pieces yet to experiment (Bill)? The 500 head has a much bigger volume than the 430 head, maybe if one was to run alcohol (methanol/racing alcohol) the 430 head on a 500 would be about right.

I need a 82/83 cr500 head. I guess this will go on the back burner till I find a head. This is in the planning stages finding parts.

Sorry for all the questions so much knowledge to find out.

You have a piston/cylinder ready to go? A piston is about $200 last I knew and then boring might be $40-80 is my guess. Lots of used bikes go to parts for other reasons than the upper end hence the top end can be put on something else. Too bad the head that came with your cylinder went a different direction. The heads get kind of banged up when the big end goes and bearing pieces get up there through the transfers.

I can bore the cylinder myself no problem. I picked up a complete bottom end and just the cylinder cheap. I'll wait to find the parts or I have an extra 430 crank and cylinder and head. Options? While I'm looking.

What transmission is in your 500 engine lower end, the 4 or 6 speed. The air cooled 430 (6 speed not sure if others exist without looking at the parts sheet) used the same primary reduction as the 6 speed 500. Later a lower ratio was used. Take the clutch off and see what condition that little gear on the back is in. I like the power characteristics of the 500 better as you can see the porting near the reed cage is two openings instead of the one on the 430. The reed cage has been discussed lately. The air cooled 500 is a quad port transfer where the 430 did not become that way until water cooled. In hind sight the guy that got me started on these bikes saved up his money and went out west a few times to high altitude. That may really be the sensible reason to have a 500.

A vertical mill, I have an Index which is a bit more machine than the standard Bridgeport does not have the travel to bore one of these cylinders. Somehow I guess you would have to move the table, That might work if the machine was new. I sent out the cylinders for these bikes. Not sure it is even worth doing it myself it as other guys I know bore cylinders like these with no problems. I did bore a Norton cylinder, kind of strange the dust like chips it makes instead of twisty ones with steel.

The dust like chips is castiron. I don't think it's cast steel. The castiron with nickel added gets harder than steel. The glaze that forms from wear. This is why discs on disc brakes are castiron on vehicles. I recently purchased two gear driven adjustable hones. With rough stones to fine stones for finishing. My sunnen gear driven hone was worn out. I could open a bore right up. No need to bore with a cutter if the bore isn't that bad. The hone will clean up a few small score marks and hold it true. I bored a lot of cylinders, v8engines, hydraulic cylinders.ect.

The late '70's and 80's husky cylinders bore easy. I bored a '72 250 and found the sleeve to be very hard material. The stones slowed up cutting when the bore cleaned up. It was the correct size. There must be more nickel in the older sleeves.

I have a LQ cooled bottom end assembly too I think it's a 85/86 era. Besides the 83 AC bottom end. I purchased a extra clutch basket with the cr primary gears too. My point is I can pick the best gears for the cr500. The clutch basket/gears are perfect. Funny how some bikes are ridden hard and some aren't. I guess no one rides a cr500 hard if your not racing.