Well I have sure has some time trying to get the right part from AC for my 2004 t660. It the spring in the rear suspension with the long and short arm and coil in the middle. Last February I ordered what AC had listed as the heavier springs for this sled pt. nos. 1604-380 and 381. Got them in and the springs were as soft as butter in summer. My 150 pound friend could bottom them out in the stiffest setting sitting on the sled. Needless to say when I sat on it it went to the botton like stepping on a pillow. So I decided to try again this year and I ordered part nos. 1704-148 and 149 which are listed as square springs like what I got factory on the sled but of a heavier wire and listed as a trail spring. When the order was placed AC did not send the part-listed it as unavailable even though inventory showed it there when order placed. So the dealer and AC decide to send me out what the book calls for overload springs- this year part number 0704-944 and 945 which are round spring like the ones sent to me last year-- and by a detailed examination are almost if not identical to the ones last year except for having the longer arm 1" shorter. Pulling on the ones from last year and this year yield almost the same force--hence saving mysled a huge headaches of trying these springs on again and getting mad--I call the dealer and he calls AC. They are working on it they say.

What I need to know is what is the heaviest spring that AC makes that will fit my sled--I had a 1997 AC thundercat with awesomely strong heavy springs and would love to have those springs on my t660--anyone know that part no.? Or any other AC part number for the heaviest spring they make?

Thanks,
Tony

How heavy is the primary rider? I assume your talking about a one up sled?
Shoot me a pm with your info and I'll check my charts.

Rick
:D

where is the rear arm on the suspension set

Originally posted by ZR Sled Head@Dec 3 2004, 09:13 PM
How heavy is the primary rider? I assume your talking about a one up sled?
Shoot me a pm with your info and I'll check my charts.

Rick
:D
370919


pm sent

Originally posted by snofrog@Dec 4 2004, 09:26 AM
where is the rear arm on the suspension set
371042

The arm on the scissors part is set to the farthest hole to the rear of the sled on the slide rail. The suspension spring is set on the tallest block setting of the three.

HTH

Tony

Tony dont know if this helps or not.... my T660 ST is pretty stiff at the low end of the spectrum.... i weigh 170 and i could not bottom the rear out when i jumped on it. mind you I have not ridden it yet to break the suspension in... but if your talking about a standard turbo then the springs in the rear should be different then the ST... Find out what the ST has and see if you can get those... the real question is can you bottom out a ZR because the rear setup is almost identical. My buddy just upgraded to an 02' ZR because he weighs about 280 and was easily bottoming out his rear suspension on a 2000 ZL. Just my .02 cents

what about checking browns for springs?? I know I went through them when I wanted a handlebar riser for my firecat,,, was able to get a factory one that was 2" higher than the stock one,,,,
so if they have that option on there, they may have others part options also,,,

Originally posted by PowderBoy@Dec 4 2004, 11:48 PM
Tony dont know if this helps or not.... my T660 ST is pretty stiff at the low end of the spectrum.... i weigh 170 and i could not bottom the rear out when i jumped on it. mind you I have not ridden it yet to break the suspension in... but if your talking about a standard turbo then the springs in the rear should be different then the ST... Find out what the ST has and see if you can get those... the real question is can you bottom out a ZR because the rear setup is almost identical. My buddy just upgraded to an 02' ZR because he weighs about 280 and was easily bottoming out his rear suspension on a 2000 ZL. Just my .02 cents
371374



The t660 trail and t660 st use the same springs..checked that already....but thanks for thinking of me....


Tony

thought i had a similar problem this fall. when i started getting sled ready for grass drags. my rear suspension felt real weak. bounced rear quite a few times and it came back. must of had air settle in rear shock. raced one day and now it's fine. also why can't you install zr sno pro springs. should be same skid.

You get my email??

Rick
:cool:

Originally posted by ZR Sled Head@Dec 5 2004, 09:57 PM
You get my email??

Rick
:cool:
371722

yes I did.. i replied....

The numbers you listed were the ones that I listed in my post above so either they sent me the wrong springs or something.....


Tony

Just measure the wire diameter of the ones you received to confirm.

TONY..............Your ordering the wrong part number, it's 1604-148/149 which changes up to 1704-288/289 .460 wire at 77 deg. You will have to trim the long leg to fit but it's no big deal.
My buddy is seeing excellent results (although a little smaller than you) using a .460 spring at 83 deg. The spring I've suggested should work mint for you being as it has a 77 deg angle for more preload.

Buy the service manual. PROPER upgrade should be in there!