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A solution to fairing scrapes

  • Thread starter Black and Swoopy
  • Start date
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Black and Swoopy

Guest
Previous owner fitted this aluminium strip with auto tape. I have scored it on track days but no fairing damage. Exhaust headers still touch but hopefully now that I have adjusted sags front and rear and put a 4mm spacer in rear, should be better.

:lick:
 

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jeff g

Guest
sag

Hi

now that I have adjusted sags front and rear and put a 4mm spacer in rear, should be better.

sag in mm please

jeff
 
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Black and Swoopy

Guest
Front-35mm
Back-20mm

Front was 50mm
Back was 65mm !!

For front I used a +-2mm washer (cheapie galvinised washer-roofing ??- from fastener specialist which fitted perfectly the diameter of the fork and the central hole fitted perfectly around the damper rod nut as well) Alternative is extra Honda spring seat washers at 4 times price but they are only bout a mm thick.

I also added 25ml fork oil to each leg which raised oil height bout 20mm and damper rod nuts were locked 2 turns out from bottom of thread (two turns "up").

For back I turned the spring C nut down bout 5 turns and made two slotted plates of bout 2mm thickness each to slip around shock mounting bolt under the sub-frame. (No need to remove shock or undo linkage nuts thank goodness.)
Rebound set at 3/4 turn out.
 
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birdistheword

Guest
20mm?

I maybe way off here but 20mm is to stiff,shouldnt u have the same sag front and rear?But how do u find it? i have been think along the same lines.But with about 30mm front and rear.Does the extra oil height help?
 
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Black and Swoopy

Guest
Howdy-
Suspension settings are a grey science. And even at the pointy end of talent, two riders with the same bike can end up with rather different settings and go equally fast. Some like the steering fast and twitchy, some like it neutral or other set ups.

My preference is for a set up that is a compromise between as firm at the back and as quick as possible steering but softish on the front (for feedback) that is still ok for the road. I also often ride two up and that is a total of about 165kgs. But then I also like to be able to do a track day without fiddling.

A few "rules" as per Ohlins and Racetech advice and what I have learned from those in the know and put into practice are:
1-Always have at least 5mm more static sag in the front than the rear.
2-About 1/3 of the suspension travel for static sag is usually a guide for a factory type default setting.
3-From 5mm to 35mm at the rear and 10mm to 45mm at the front would be the total range usually considered. For "sporty" handling about 25/30mm rear and 35/40mm front would be most common.
4-The more the rear is raised (sag reduced) compared to the front, the quicker the steering.
5-When a spring is shagged, such as when the static sag at factory default preload is half or more of the suspension travel, get a new spring made for your weight. (Racetech are excellent for this). Jacking up the preload will just make the ride harsher and hardly compensate for bottoming or improve handling. (My rear spring is nearly history-probably because the previous owner pulled a trailer and rode two up.)

I would suspect a new 'Bird would be close to right brand new except for a turn or two down on the preload C ring at the back and a 4mm to 6mm spacer under the rear shock mounting. However, if you usually ride solo and don't weigh more than about 70kg and are not likely to explore serious lean angles, there would probably be no serious need to change anything until the springs start to get tired.

I very much recommend all 'Bird owners establish what state their suspension is in and whatever it is, work in the direction of a good setup, preferably a quicker steering option. It is quite amazing how well an already good handling and nice steering design that it is can be transformed into something quite stunning for such a large and fairly heavy bike.

Make all setting changes conservatively and take the time to ride long enough after each adjustment to think about what has changed.

There are many other aspects that can be discussed (preferably standing next to the bikes in the back yard with a few frosties and a barbeque on the go), so please feel free to question further.

:beer: :beer:
 
E

EdCBRCastrol

Guest
Black and swoopy
looks like you're the man to ask about suspension!!
I have just replaced my spring and shock, have a new factory shock and have lowered the spring collars 4mm, have also fitted a 6mm spacer.I am just under 16stone so does that sound like a sensible adjustment?
 
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Black and Swoopy

Guest
Howdy EdCBRCastrol,

Hmmmmmmmmm-16 stone is about 185lb or 85kg ?????. Trying to remember my schooling b4 I was metricated.:}

4mm down could be about the 5 turns down I have done, but remember my shock was a bit shagged from trailer towing. I used a 4mm spacer. I am 95 kg BTW (should be no more than 85 but thats another story).:mad:

You have a new shock and weigh less than me...........................I would be guessing you have set up a pretty aggressive sag there, prob about 10mm or less. Plus a 6mm spacer so you should have the steering about as quick as you could ever want it.

But, there is no substitute for checking the sags, pref b4 u make adjustments.

Also, check rebound adjuster-prob need to close it a bit due to the extra preload u put on the spring but I don't suggest u use less than 3/4 turn out from closed. U might find with the set up on the rear u have now that the front gets loaded too much, so check the sag there as well and let me know how it feels. The front by nature has too much compression damping and a weakish spring, so not a lot can be done, but for safety sake a few tweaks can help, but unfortunately usually at the sacrifice of a slightly harsher ride at lower speeds over sharp little bumps.


:beer:
 
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EdCBRCastrol

Guest
Cheers black and swoopy,
16stone is dead on 100kg, i will check sag with proper measurement but it appears to be about 25mm ish when i sit on the bike, certainly seems a lot easier to get round bends.
 
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EdCBRCastrol

Guest
At what point on the rear should i measure sag, just thinking that the travel is in effect in an ark so will get different measurements at different points, have measured 28mm sag at tip of tailpiece.
 
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Black and Swoopy

Guest
Make sure it is static sag u measuring (bike under its own weight).

Just take an imaginary vertical line up from say the chain adjuster (easier as it has a definite edge and also standard to measure from end of arm/ axle where most movement is). Make a temporary mark or find a point on the tailpiece to measure to from the swingarm.

It is a bit of an arc, but i doubt whether it would matter much. The main thing is to get in the ball park. Some bikes would be measuring 10 or 20mm too much static sag and this test will detect that good enough. Also, for the 'Bird, we can all replicate this sort of measurement and even though it might not be theoretically perfect, it will work in practice.
 
X

XXscraper

Guest
someones a bit knowledgeable here

and it aint me :goofy:

Help please what the fook is static sag, is it the travel from when there is no weight on the suspension in question ie lift the end of the bike into the air and then put it down again and messure the gap?


PS The aluminum fairing strips might be more of a solution to falling offf and really scraping your bike, what happens when they dig in, at least fairing shaves off :eek: Wouldnt risk it myself and besides it looks quite cool :-:
 
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Picquet

Guest
Rear 6.0mm spacer.....

Hi, Folks.
I am thinking of doing the 6mm spacer thing .
Having m/c shop facilities I could make one myself.
Are these spacers simply large `washers`or do they have some shape to them ?
When on the centre stand, if I undo the shocker top nut, will the shocker drop enough to push a `slotted`spacer into position ?
Thanks.
 

Judge Dredd

Been there, and had one
Club Sponsor
cut slots into them

and yes they will slide in. If you stick a shovel under the rear tyre you can then lever the tyre up and still have both hands free to ensure the shocker goes back up and do the nut up.
 
X

XXscraper

Guest
couple of things

I had probs with undoing the shocker top nut - i had to anglegrind off a coulpe of mm from the 17mm socket because not much of the nut is available.

I had to jack the bike up and put some wood under the centre stand to get clearance.

Tighten the chain up and note the chain wear indicator position. If you dont do this your chain will reach the 'replace chain' position sooner than it should. Once spacer fitted, tighten the chain up again and messure its new position, Make a note of the difference for future reference.

Finally, you might want to adjust your headlamp cos you have just lifted the back of your bike by 6mm so the beam will be affected too - it wont be a problem until you are out at night and you go fook me cant see further than 10 feet.

Happy counter steering - it dont arf make a differece :yo:
 
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