Originally Posted by
valve_timing
will 25mm tires fit the 89 im master
Depends on the tire and rear brake.
No problems with
Continental Ultra Sport II 700x25 on my '89 Ironman Expert. Excellent value in a very affordable tire. I've ridden 'em for more than two years in 700x23 and 700x25 on my Ironman.
But
Continental Grand Prix Classic skinwalls (700x25 only, no other sizes available) just barely scraped the underside of the rear brake bridge on my Suntour GPX brakes. Carefully adjusting the rim to eliminate a very slight hop helped. But any time I rode through a puddle or a slight bit of sand or gravel, I'd hear scraping. Mostly I just had to ride the tire to wear it down, mostly on the indoor trainer. No problems the past 2-3 weeks. And a different brake might have enough clearance.
But those Conti GP Classics will go back on my '93 Trek 5900 after I finish putting that bike back together. No problems there.
The difference between the tires is the height, not width. Conti Grand Prix classics have a very 1980s style tread, with raised center tread with sipes, and shallow chevron tread on the shoulders. It's cosmetically appealing but doesn't ride any better than the lower priced Ultra Sport II, which are basically slicks with Conti's peculiar arrow shaped doodads on the shoulders.
So 700x25 tires that are slicks or have a slight tread but no raised center tread should be fine.