T250 / T350 fork spring sag

[jabcb]

The 71 T350 shown in my avatar is back up & running. Needed a new top end. Now runs good & I've started breaking it in.

The fork springs sag badly -- most of the travel is used up when I sit on the bike. What's typically done about this? Air caps? PVC spacer? New aftermarket springs?

[5twins]

The cheap fix is PVC spacers. Make sure to use a washer between them and the spring. Aftermarket springs are usually a good fix but finding them for your model may be difficult. Another easy upgrade is using slightly more than the original amount of fork oil. This adds an air spring effect. Most aftermarket springs come with instructions telling you to set the oil level at 6" from the tube tops, springs removed, forks fully compressed. I would check what level the stock amount of oil gives you and experiment from there, going no higher than 6" from the tops. If you put too much in, you can blow the seals when you hit a big bump. An extra ounce of oil made a major improvement to my XS650 Yamaha forks.

[rbond]

Another trick is to put in valve springs from a Honda 100/125. I did that on a TS100, worked pretty good, but getting the fork caps started was a booger.

[5twins]

The best tool I've found for installing fork caps is a T handle. You can push down and turn at the same time. Motion Pro makes T handles with 1/4" and 3/8" drives on the ends. Turn your whole socket set into T handles with one $10 tool.

[jabcb]

Valve springs look like an interesting option. No sure how I would go about figuring out which ones to use.

Anyone know what the nominal dimensions are for the T350 springs? (71 T350 has internal springs.)

Progressive Suspension lists their fork spring specs: http://www.progressivesuspension.com/pdfs/7100-105.pdf" onclick="window.open(this.href);return false;
Would any of them work?