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If the rear spring can be wiggled in its seat as you say, that simply means that the preload (the locking screw nuts above the spring) is at the minimum possible setting.

You feel that the right fork is 1.5mm too high? Easy enough to measure, or take a pic. Wouldn't be noticeable on a ride. The 2 forks will never be 100.00% identical in operation anyway.

As far as your handling problem, assuming the frame is ok, my money is on the tires F&R. At a certain point they will go "off", even with tread remaining, or possible tire impact damage.

PS: double check the torque on the head races.
 

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G'day Extermin8tor,

I have a 2005 with 129,000kms.

Tyres are Michelin PR4...... sadly they are over 6yrs old and only 5k kms...... look new, feel new (garaged and kept inflated ready to roll)....... but I wouldn't do a big trip or high speeds on them....... intending to fit newies if and when I ride it more than around the block o_O

Front forks..... 484cc of Motul 10wt each leg..... usually changed with new tyres as wheels are out, and that's at 20k kms when the tyres are knackered. (same as you, I take the rims out for tyres, because i can grease bearings, check wheel balance etc myself.... but I can't change tyres........

Rear shock original on mine too - BUT - it has only done 13k kms of work as I usually have an Ohlins shockie installed..... it's on the table waiting for me to get it serviced, so I have the oem fork springs and shock back in the BB, and it handles fine. Not as good as the Ohlins springs and shockie, but still very good. Yours will be stuffed at 75k kms.

The BB is great in corners too, but like ALL bikes, it must be set up properly, nothing extraordinary, but properly.....

Ahhhhh..... here's a clue...... tyres 42/42....... bad, very bad, horrible in fact....... 20years ago Honda thought they knew what they were talking about when they thought they built the fastest proddy bike ever....... I tried their advice for the first week of ownership...... until it rained and the roads went cold and slippery..... and I always wondered why my tyres made a scary 'pinging' noise when I struck the odd bit of road chip...... then I spoke to my pro mechanic cousin about it and he said..... FFS use 36psi F and 38psi R like every other high performance road bike....... and now more than ever, when other bikes make the BB look feeble, they are using 34-36F and 36-40R depending on load. Track guys will use 30-32F and 34-36R (cold set) anyway, so using 42F 42R is unnecessary and may even be contributing to your handling issue. Trust me, I know what I'm saying...... 45yrs riding, over 1 million kms, heard all the BS about tyres before but I've never had any issue doing what the pro tyre shop fitters have recommend over the 20 year 'out of date' Honda manual specs (y) .

(I get 35C days in summer down here in Brisbloodybane, and if BB had TPMS like my KTM SDGT had, you would see tyres rise 4-5psi at highway speeds, which is normal. eg I ran 34F 36R in my Kato on long interstate precovid tours in 35C temps, my hot pressures while riding were 39F and 42R anyway..... and I still got 15k kms out of the Michelin Road 5's I used..... which are way softer than PR4's, but prob harder than your M-Sports).

So I'm inclined to think your tyres are ok but you should be running more normal pressures, however there may be an issue with the Steering Head Bearings and or a mismatch with the rear shock spring preload/shockie rebound damping (or total lack there-of at 75k kms if it has never been rebuilt).

It's best to install forks with the BB on the center stand or on a race stand, not the side stand. I use an old race stand through the swing arm axle or the rear axle and a car jack under the front of the sump..... being careful to make it stable. The forks need to be level with each other, the springs and spacers inside need to be the same as they came out, the fork oil needs to be equal height........ aaahhhhh, i think i just clued in to the real issue here...... it was always a bitch to get ALL of the old fork oil out at drain time. So much so I used to flush my forks out with a softish cleanser like diesel or kerosene, and work the fork damper units (like milking a cow) until they had no oil inside. They hold a lot more oil than you think, so I suspect your forkoil levels are uneven! I have muffed this myself.... on a set of Kayaba USD forks in an FZR1000 Genisis Yamaha.... thought the oil had drained out over several days, but when I filled the spec amount of oil into each tube I was basically overfilling the forks......... a trap for players, a lesson learn't the hard way ;)

So go back and test the steering head bearings (prop the front wheel off the floor so you can do the push pull and L-R feel test..... any play or notchy feeling is bad news). Also, the handle bars should swing easily side to side and hit the stops firmly..... if they are too tight they will resist like as if they had a steering damper attached.

Then check the rear shock rebound damping..... a crude test is to hold the BB upright by the rear seat handle or a sturdy luggage rack (if fitted) and shove down with force and 'feel' the compression damping, then note the rebound damping as it springs back to full height....... if it seems to spring up with no resistance, the oil in the shock has the consistency of water. If when you sit on the bike and the back end sags down more than about 30mm, you could have a badly set up shockie or if it is original and has done 75k kms, a worn out shockie and collapsed spring. Best to buy a new shockie, unless you have a local version of my "RAD" shockie rebuilders who can advise if they can re-spring and re-build and re-oil that supposedly non re-buildable dampner.

It won't be age that's making the BB suddenly feel dangerous to ride..... it will be in the detail.... oil levels, alignment, etc..... so go over your workmanship, check check check, and if you have fitted a 6mm spacer, remove it as the 04-05BB's don't need the rear end raised to corner properly..... only the earlier models had that issue. I raised my forks 6mm through the steering clamps when I fitted Helibar risers and my BB steers beautifully, and when i've got my tail up, I'm hard to keep up with, bumps and all, so get cracking and good hunting :D

Your BB should come out perfect if everything has been installed correctly - use the 02 workshop manual in the resources section for clues..... even putting the front axle in needs a special feeler gauge...... nothing is ever simple...
What's FFS?
 

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Oil levels need to be checked with the forks off. Springs out and tubes bottomed. Then the level is measured from the top of the tube to the liquid level. If these are off then the forks will compress differently.
The rear spring shouldn't rattle around on the shock even at full drop. Unless its worn out. What are your sag measurements with the bike on it's own weight versus you setting on it. You want about 30mm of difference. I'm suspecting you way over that without any spring preload.
 

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No No its all good I appreciate the info.

I think you're onto something - I need to check my oil levels in the front forks with it on the center stand. I did them individually. Sadly as they are not symmetrical, I couldn't weigh them on my scales.

I also feel like the right fork is 1-1.5mm too high.

I have a new rear tyre coming - that should help.

I will lower my tyre pressures to 36/38 and give it a go - it's always hot here so I'm sure they will warm up and increase the pressure.

Also - when my bike is on the center stand, the rear shock spring can be gently wiggled around in its seat, is this normal? I assume its because the swingarm is allowed to travel as far as it can go?
The bump test is one that I'm not so good at, I think ultimately I need to cough up for a rear shock, I am just waiting on some spare $$ and to see if there are any other things I can do in the meantime.

Frame wise I think I'm okay, everything seems fine apart from the welding of the headlight stay mount.
Thanks Ext,

Sometimes I get a bit carried away....... so long as it's not in an ambulance........ or a straight jacket :ROFLMAO:

That spring shouldn't be loose on the shockie even with the bike on the center stand. It sounds like it's original (red) and has done all 75k kms and has lost it's errrr 'spring'........

PS I know this because I was riding with pillion (when I had a back seat commander/financial controller..... no she was quite ok actually, loved the bike more than me :ROFLMAO: ), and as we hit a bridge joint she heard a rattle (I wear ear plugs so didn't 'ear' it ;) ), but I certainly felt it, as instantly the handling was :poop: - like I had a rear tyre deflation.... I pulled over,.. all was ok but it had me 'rattled' so we went back to a servo, slowly, wondering what was wrong. At the servo I realized I could wind the spring preload up to max - it was an Ohlins shock with remote preload winder - and all was good on the way home. Later on I took it to my shockie service guy at RAD Shockie repairs and he put a new spring on and changed the oil etc. Shockie was like new again, ready for another 80-100k kms.......

So springs do wear out....... more quickly if the bike carries it's max load most of the time.

If the spring is sagged then the oil in the dampner will be like water and the rebound-compression will not be working effectively, so it's time to consider a rebuild or a new shock with a remote adjuster (y) . Same goes for the front springs..... they can also sag with age.
 

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For F**K Sake
AHA! I am truly a fossil! LOL!

With regard to the tire pressures, I think that Aussie Dave is spot on. Reg Pridmore, in his book Smooth Riding the Pridmore Way recommends 32/32 for bikes weighing 400-600lbs and 36 Rear and 34 front for heavyweight bikes with solo rider. This is for street riding even though the advice is coming from an AMA Superbike champion.
 

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Discussion Starter · #27 ·
Oil levels need to be checked with the forks off. Springs out and tubes bottomed. Then the level is measured from the top of the tube to the liquid level. If these are off then the forks will compress differently.
The rear spring shouldn't rattle around on the shock even at full drop. Unless its worn out. What are your sag measurements with the bike on it's own weight versus you setting on it. You want about 30mm of difference. I'm suspecting you way over that without any spring preload.
Theres only a small sag, about 2-3cm. I am only a skinny bloke, about 65kg.

I did notice the spring-preload double collar thing is wound all the way back.
The owners manual doesnt state how to set it correctly. Is there a number of turns or mm/cm of turns that the double collars need to be turned?
 

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Ok
So your in the range. Just bring both the collars up till the spring is trapped at full droop. Then recheck your sag again.
 

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Theres only a small sag, about 2-3cm. I am only a skinny bloke, about 65kg.

I did notice the spring-preload double collar thing is wound all the way back.
The owners manual doesnt state how to set it correctly. Is there a number of turns or mm/cm of turns that the double collars need to be turned?
Shock absorber spring preload length 209 millimeters/8.2 inches per factory manual. Measure end to end of spring.
At that many kms, time for a new shock imo.
 

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Excellent has a very good point. Check spring free length (unloaded) if it doesn't meet that minimum it's done. Factory shocks damping systems are typically gone around 25 to 30,000 miles anyway.
 

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Hi peeps,
I have a 2004 bird with 75000km.
New front tire (Michelin Sport). Rear is probably 5-8000km old - still feels soft, no dry rot, a little squared off. 2017 date code.
Front shocks - oil changed.
Rear shock - original.
Front/Rear 42psi.
Average temp during day here 35c - so hot roads.

I noticed I was taking a sweeping curve at about 120-130kmhr whilst accelerating gently and the bike felt like it wanted to tip over once I started leaning a little.
It was quite a scary feeling.

I'm kind of terrified riding this bird in a spirited fashion, I've had lots of big bikes, 1200's, 1600's, BMW, Honda, etc. Never felt so unstable?

Anyone have advice? I have done all the work myself so perhaps torqueing issues and height of forks etc can play up? I did make sure to tighten the triple tree fork clamps with the bike on the ground on the side stand.

Should I swap the rear tire and see? It's getting old. The front that was matching had dry rot so I changed it.

Is it sign of a fooked rear shock? Is it worth adjusting the old worn one? How do I tell its completely fooked? Is that guaranteeed at 17 years old?

Cheers in advance.
This happened to me 6 months ago. Out riding on the highway on a breezy day... when a crosswind caught me while I was in a gentle turn. Felt like I was going to tip over. The rest of the day the wind picked up more and more. One of the most unpleasant riding days I've ever experienced. Had me thinking that maybe it was time to give up my passion. Riding for me is like therapy. If I don't ride for more than 3 or 4 days, I start getting seriously depressed.
When the day was done I checked my tires. Was running PR4's. Back tire was slightly squared. Didn't seem like it would be enough to make a difference, but I made the appointment and had a new set of PR5's installed. Like night and day. Rides like it is on a rail. Still bothers me to ride in wind, but no wind and I'm riding like I was meant to. Sometimes it is the most obvious fix.
 
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