View Full Version : FJ front tire question

The Big Spank Daddy
July 30th, 2002, 01:27 PM
I recall when they first came out in the mid '80s one of the bike magazines complaining about front tire wear and cupping. Now when I got this bike it had an ME880 on the front and it was cupped really bad.

I installed an ME33 and have keep a close eye on the tire pressure. 32 by myself and 36 two up. I have also serviced and maintained the forks since having it and change the setting anytime I ride two up accordingly and back dowm when by myself. I use the front brake hard and rarely use the back brake.

I took a close look at the front tire after this weekend and it is showing some pretty good wear but no cupping after 11K miles. It is about .020" from the wear bar/marker. What kind of experience have you other past FJ owners experienced in this area.

Scott Dennis
August 5th, 2002, 08:54 PM
Chris, The early FJs (the ones with the 16" wheels at both ends) were notoriously sensitive to tire profile and wear. Depending on the tire brand, front tires would either cup or get a very weird triangular wear pattern just off the center crown of the tire. I replaced several that appeared to have plenty of tread life remaining trying to get the neutral steering balance restored.

The real evil issue, however, was the handling quirks that a worn rear tire would cause. As soon as the rear got even SLIGHTLY squared off, the steering response would start getting very numb and uncomfortable. To me, it was slow to move off-center and then quickly transitioned into a frightening sensation of understeer.

My solution (admittedly this is extreme) was to put a complete FZR1000 front end on mine, and graft on an early-model GSX-R750 swingarm/wheel. The forks were a bolt-on; the rear required some pretty extensive machine work that Lonny did a superb job on. The finished package, however, was SWEET handling and much better balanced than the stock configuration. As an added bonus, the handling remained peg-dragging predictable as the tires wore. We'll get together over a beer sometime and I'll tell you what happens when you drag a saddlebag full of dirty riding clothes! smile.gif

Ride safe,

[ August 05, 2002, 09:55 PM: Message edited by: Scott Dennis ]

August 6th, 2002, 09:19 AM
Does Race Tech or Progressive suspension make stuff for the FJ's? Seems like this might be a cheaper way to go. After all of these years a complete rebuild might make a big difference.

Of course if I got 11k off of a front tire I'd be one happy camper! smile.gif

Scott Dennis
August 6th, 2002, 10:23 AM
Peter - Good point. I have this bad habit of seriously over-engineering solutions to simple problems. Example: The doghouse in the side yard is on a slab, with piers. Brick to match the main house, plus full roof decking/shingles. HardiPlank eaves & soffits. Oh yeah, and it's floored with ceramic tile to match the kitchen.

So... you're exactly right. A fork rebuild with Progressive springs, and a fresh set of steering head & swingarm bearings is definitely phase one. Depending on the mileage/condition of the shock, it may be a candidate for replacement as well.

Louis Reinartz
August 6th, 2002, 11:06 AM
Did you get the dog house addition approved by the home owner's association???

Scott Dennis
August 6th, 2002, 11:43 AM
Actually, yes I did. The fact that I'm on our architectural control committee probably helped. smile.gif Still, I caught some grief for building a "permanent structure" in the easement within 20 feet of the side property line.

August 9th, 2002, 06:39 PM
Progrssives on the front and adapting a wheel from an F2 makes a fairly nice package also. The 17" rear w/good rubber really changes it up but not as work intensive as Scott's solution.

The Big Spank Daddy
August 9th, 2002, 07:18 PM
Yep, 16" wheels on both ends. Front already has Progressive Suspension springs. It has taken me some time but I pretty much have the front end sorted out.

The rear is were I have a problem. The spring and dampening are adequate but the rebound is way to stiff/slow. I'm not sure but I believe the rear shock and spring are not stock. This winter I plan on stipping down the whole bike and powder coating the frame black or red. At that time I plan on rebuilding the swing arm and links with new bushings and adding grease fittings.

You are absolutely correct about the rear tire profile. When it started to wear a little flat it was very "twitchy" between the flat area and the side tread. This BT45V that's on it now has less tread depth on the side to help counter act that situation. The center is just now starting to show some wear after 3K miles and it may take about another 1K to 2K miles more to see if this design actualy works.

August 9th, 2002, 07:23 PM
If I remember correctly, to use a 17"er off an F2 only required making a couple of spacers, I believe a 160 or 170/17 was the size of choice after this, We used ME-1s so you can see it's been a couple of years.