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Discussion Starter · #1 ·
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.
 

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Yer sound a bit like rear tyre needs a change, check you wheel bearings front and back by getting the wheels off the floor, grab the wheel 3 o'clock and 9 o'clock position and check for play, also check swingarm as well, also if the front wheel is off the floor, slowly turn the handle bars left to right and check for any notchy ness, if there oem ball bearing type they mite need a change if the bars sort of self centre when you just go either side of centre bar position. Rear shock mite need attention as well, check for leaks, and bounce the rear end to see how fast it responds, if it bounces really fast instead of returning and stopping then yer shock could be done.
 

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I can relate to this. In fact, I have used exactly the same words - terrified - when describing the corning sensation of a BB.

I think the problem relates to a few things. Please allow me to elaborate. Firstly, the rear shock. On my Bird, the rear shock is old and needs replacing. When I go over bumpy roads on this shocker, the bike bucks up and down. The sensation for the rider is to get thrown upwards in the seat. This completely unsettles the bike during cornering when the corner is not completely smooth. If you go faster in a lower gear, knees gripping the tank and being loose on the handle bars, it feels better. But the problem is the old worn out rear shocker not doing its job so you’re not fixing the problem, just living with it and compensating with your body and riding style.

The other thing about this bike is its high centre of gravity. It gives me the horrors at low speed, especially full of fuel. Again the bike feels like it will tip over when turning. And it will, if your not careful. What I did was to practice low speed manoeuvres over and over in car parks. These skills translated well to the road, at low and high speeds, and built my confidence when leaning into corners. I also recommend finding twisty mountain roads and riding up and down them again and again getting to know the bike at different speeds and in different gears.

In summary, what I have come to accept is that this bike is build for speed, not necessarily corners. The top heavy nature of the bike coupled with worn out suspension can conspire to make it feel dangerously unsettled in corners. My remedy is two-fold, spend time bonding with the machine and hopefully your confidence will improve as you get to know the bike’s limits and feel. Failing that, start changing stuff until it improves, like tyres, fork springs, rear shock etc.

I am upgrading my front suspension to Jamies D’s cartridge kit next year. I will also buy an expensive rear shock, as well. In the mean time, I will continue riding the bird and getting to know it limits even though it desperately needs upgrading.

Nato.

P.S. Please understand that I am not an expert, this is a personal onion based on my own experience riding a Blackbird over the last year or so.
 

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I'll bet it's a series of contributing factors. When you say Michelin sports what model are you referring to? Are they both the same version.
The rear being squared off will exhibit the characteristics your describing.
I run Bridgestone T31's on mine now and they nothing like the Michelin Roads I used to run. They tip in much quicker but never loose footing. Once you tell us the tire model it may shed more light on your bikes handling.
 
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Sweeping bends at 120-130 Kph are the sweet spot for my Bird, so your experience and mine are polar opposites. I have replaced rear shock with a rebuilt one in last 20K, as well as fork springs and fluids. But even before then, it wasnt too bad in corners and I never felt it would tip over (except in carparks). Suggest your rear tyre should be replaced if its squared off. Your shock will almost certainly be toast. Do you have a shim in it? is the shim too big? (i.e. > 6mm ?). Are forks at right height?
 

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The Blackbird is great and well balanced at slow, medium, fast and stupid speeds. You say you've owned numerous big bikes, so if this one terrifies you, then something is very wrong and it should be looked at by someone with an experienced eye. That sounds a bit blunt, but you did use the word 'terrified' (y)
 

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You've changed your front shock oils.
The oil thickness and level will make a difference to the way your bike tips in to the corners.
If the front of the bike sits or rides lower than before, it will turn in quicker.
 

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Discussion Starter · #8 ·
The Blackbird is great and well balanced at slow, medium, fast and stupid speeds. You say you've owned numerous big bikes, so if this one terrifies you, then something is very wrong and it should be looked at by someone with an experienced eye. That sounds a bit blunt, but you did use the word 'terrified' (y)
I reckon that's a good idea. I know its been in an accident and the headstock mounts have been 're-welded' on onto the frame. Let's hope everything is straight.
 

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Whoa whoa whoa. Were was it welded? And again what tire model are you running. If your saying the front stem section was welded back in. Then you need to take it a frame shop that has the proper equipment the verify that everything is back in alignment and at the correct parameters. Or you could be in some serious trouble.
 

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Discussion Starter · #10 ·
Whoa whoa whoa. Were was it welded? And again what tire model are you running.
The aluminium extrusion that the two bolts that hold the headlight/cowl fixture bolt into.
The headstock seems untouched. The accident must have sheered off the nose cone just at a guess.

I'll check, I know the rear is Dunlop RoadSmart 2. The front is a brand new Pirelli of some sort - sports touring
 

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Ok so just cowl brackets. Whew I'd still
The aluminium extrusion that the two bolts that hold the headlight/cowl fixture bolt into.
The headstock seems untouched. The accident must have sheered off the nose cone just at a guess.

I'll check, I know the rear is Dunlop RoadSmart 2. The front is a brand new Pirelli of some sort - sports touring
Ok whew then you should be safe.
Now the above is most likely your issue. The Roadsmart is a rounder profile I'm betting than that Pirelli you have up front. Combine that with the squared off rear and the transition from upright to turn in is going to all wacked at best.
 

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Ok so just cowl brackets. Whew I'd still

Ok whew then you should be safe.
Now the above is most likely your issue. The Roadsmart is a rounder profile I'm betting than that Pirelli you have up front. Combine that with the squared off rear and the transition from upright to turn in is going to all wacked at best.
Beestoys, you say "Ok whew then you should be safe", but don't forget he's owned big bikes before. He states "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?" I'd be taking it to an experienced mechanic to look over and diagnose (y)
 

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Beestoys, you say "Ok whew then you should be safe", but don't forget he's owned big bikes before. He states "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?" I'd be taking it to an experienced mechanic to look over and diagnose (y)
Agree Aus
Exterm
Check the frame head area for signs of cracks around the races just to be safe.
 
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Discussion Starter · #16 ·
I know I'm sounding over cautious, but make sure the tyre fitter knows what you're feeling and that he casts an eye over the bike to make sure it's ok. Good luck and hopefully the tyre fixes it !
Cheers, I just take the wheel off the bike and drive it to the bike shop as they are booked out for 4 weeks year round otherwise, then they scratch the heck out of rims if you just bring the bike to them. They are the worst in the country, and I've tried 2/3 of the major bike shops in Darwin.

This way I drop the rim and come back the next day or 2 and its done, rather than leave the bike for 10 days, come back and its not done. (Yes Darwin is crazy),

I'll check all the alignment and the forks, etc once the tires are fitted.
 

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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.

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...
 
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I reckon that's a good idea. I know its been in an accident and the headstock mounts have been 're-welded' on onto the frame. Let's hope everything is straight.
Oh groan..... I wish I had read the whole thread instead of spilling my guts above....... crash damage, possibly dodgy repairs...... you may need to have the frame checked and straightened....... it's a specialist job done in a proper frame jig. just looking at it won't reveal any evil twists or fractures. We have a frame specialist here in Springwood but that's no use to you up there in the top end...... who do your local racer guys go to to make their race bikes nice and straight?

:whistle:
 

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Discussion Starter · #20 ·
Oh groan..... I wish I had read the whole thread instead of spilling my guts above....... crash damage, possibly dodgy repairs...... you may need to have the frame checked and straightened....... it's a specialist job done in a proper frame jig. just looking at it won't reveal any evil twists or fractures. We have a frame specialist here in Springwood but that's no use to you up there in the top end...... who do your local racer guys go to to make their race bikes nice and straight?

:whistle:
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.
 
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