Getting a Ulysses to handle like an XB*R

[John Vreede]

Hi guys
I'm about 80-90% there but its not completely to my liking yet, for which I'd like some feedback.
Firstly what worked and what didn't:
- Checked the bearings per advice above. The wheel bearings were ok but there was a SLIGHT tendency for the front wheel to self-centre. I've felt damaged head bearings before and the they clicked from indentation to indent on the race, this was smooth, not like that at all, even if it did swing to the centre, so I figured it was good enough if not perfect.
- When cornering the bike didn't turn in fluidly and I seemed to have to push back on the inside bar to hold it on line through a turn.
- As mentioned above, I figured the shock needed rebuilding so booked the bike in with a respected suspension guy.
- Just before delivering the bike to the suspension guy, I figured maybe it was not so smart to go with headset bearings that were not perfect, so I replaced them with OEM parts. What a difference! Now the bike just flopped into the turns like the front tire was flat, even though it was in mid -30's psi. I don't know what the actual pressure was, because every gauge I used read a different number!
- Whatever, pumping the front up to an indicated 40psi seemed to cure the 'flopping in' just like it did on my old dirt bikes. No wonder I had to push on the inside bar, the duff head bearings were masking the flopping in.
- The rebuild of the shock and front forks went ahead anyway, since I wanted to know what effect that would have. They re-shimmed both rebound and compression stacks on the shock and both fork legs, and added new single rate springs both ends as well as the normal seal replacement. He also confirmed that shocks were supposed to operate above 60C (140F) and the underseat heat on the Buell would just stabilise the shock temperature more quickly. Anything less than about 100C (210F) is OK.
- He set it up with 53mm sag to give the same ride height I given it to him with. Its more sag than the books say is desirable, but I'm happy with it as it gives me a more compliant ride (more extension travel as a proportion of total travel) since I don't hit bumps as fast as racers, so long as it has enough rebound damping to prevent wallowing, which it now does.
- It doesn't nosedive like it used to when the brakes are used hard, the extra control is really noticeable (there was a weird wear pattern on the rear tire where the trailing edge of the tread blocks was worn more than the leading edge. The suspension guy told me was from too much dive in the from forks unloading the rear tire in braking). (Edit Apr18: Chris Mitchell said that this wear pattern is characteristic of big vee twins. That makes more sense to me at the pattern was right out to the edge of the tire on both sides; nobody brakes hard at the limits of lean!)
- The shock now operates in the design range for rebound and compression damping.
- He drilled and tapped a fill screw into the banjo of the hydraulic preload adjuster and added oil to restore its full range of movement.
- Other than that there is not a lot of noticeable difference for all the money spent, the traces on the shock dyno were very similar so even worn the Showa shock had aged well.
- The tires are well worn but even over the whole tread, no hint of flat spots.
- The suspension guy thought the tires should operate at 32f/35r psi but it still felt like the front tire was flat so I'm back to 40f/42r psi on a gauge I calibrated off his $300 race quality pressure gauge.
- He also gave me a ranges of suspension settings for all parameters to experiment with including dropping the fork legs down through the triple clamps to try to slow the steering up. He also told me the order to make the changes in, and a process to evaluate them, which I can post if anyone is interested.
- So far I've only tried the tops of the fork legs flush with the top triple clamp (about 20mm (3/4") drop) but it made no difference to the turn in, I still need tire pressures at 40f/42r to get (nearly) neutral steering.


My question is do other Uly owners experience having to stop the front wheel turning in too far when cornering at the manual-stated (36f/38r psi) tire pressure, or is 40f/42r psi (or even higher since its not entirely gone away) normal?
Rgds - jv

[jl551c]

Q: My question is do other Uly owners experience having to stop the front wheel turning in too far when cornering at the manual-stated (36f/38r psi) tire pressure, or is 40f/42r psi (or even higher since its not entirely gone away) normal?
Rgds - jv[/I][/B]

You may have more riding experience than me and are able to feel delicate differences in steering with tire pressure, but I do not ever have to stop the front wheel turning in too far when cornering at any PSI in the 36/38 tire pressure range + or - a couple degrees. These are pretty short wheel based bikes though and in my experience turn like they're on rails. I'd be interested in knowing how your bike feels with a new set of tires.

[John Vreede]

I have a friend who has forgotten more about bikes than I know and when I questioned him about excessive turn-in his immediate response was "Get new Metzeler Z8 tires in the standard sizes and I guarantee the turn-in problem will go". He said NZ roads have much higher camber than almost everywhere else in the world and need to run at higher pressure (40-42psi) to compensate. Also said that the Uly won't have that 'planted over the front wheel' feel of the XBR's due to its geometry.
So a new set of Z8's are being fitted Thursday. I'll let you know - jv

[John Vreede]

The new tires have fixed the excessive turn-in, even at 38f/40r psi. It turns absolutely neutral, goes where it should, with no more or less lean than required.
I'm amazed at how much difference the new tires made considering the old ones were not worn out. The front had about 1/2 tread left and the rear at least 1mm over the wear bars , maybe a bit more in the middle, and they were evenly worn with no flats.
I think the biggest culprit in the poor handling was the steering head bearings. These masked the fact that there was also an issue with the tires affecting the way the bike turned in. Most of this problem could be overcome by pumping them to 40/42psi but that's harder than I'm comfortable with given the bike is relatively light with large section tires. Although my mate Chris specified Metzeler Z8's for the Uly, I'm pretty sure that any good quality tire would have done almost as well.
The expensive shock rebuild and suspension set-up ($1800NZ) didn't actually make much difference to the handling, though I can brake harder with more control because of it.
My learning from all this is that steering head bearings and tires are critical to a Uly. If you're chasing handling problems and either of these show any wear, even if you think its acceptable wear (as I did), then change them before looking at anything else like suspension rebuilds. In fact , at <$100 to replace steering head bearings , if you've got handling issues replace these anyway before you try and diagnose any further.
Thanks to Chris Mitchell from Promoto Yamaha in Taupo NZ and to everyone who responded - jv

[Cooter]

Looks like post #6 nailed it perfectly. That guy deserves a beer! LOL. Glad you got it to where you like it.

[John Vreede]

[QUOTE=Cooter... nailed it perfectly[/QUOTE]

Hey Cooter, sometimes when truth stares you in the face, you say "Go away, I'm looking for the truth!"
When I read your post I thought 'I've checked the bearings and they're sort of OK and the tires don't have have flats' so had to learn the hard way.
All good now, a little wiser and poorer - jv

[Cooter]

I'm guilty of that too, just teasing