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bladebird
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Discussion Starter · #1 ·
Hi all had the new springs
top and bottom bushings
new seals
and 7.5wt oil
and dropped the forks thru a bit unfortunately it was rainig on the way home
so didnt get a chance to test them but they do smooth the ride out and it feels
as if it will turn into corners quicker
 

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bladebird
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Discussion Starter · #2 ·
HI all quick update done my normal 14 mile ride to work and back and knowing the roads
and holes and drains etc i purposely road on the bad bits and i must say its a far
smoother ride
 

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Does the bike feel twitchy at all? I've had hyperpro sprngs put in and the front feels too stiff and light and twitchy now. Do you think taking some oil out would help? Next bike will have adjustable suspension!
 

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Does the bike feel twitchy at all? I've had hyperpro sprngs put in and the front feels too stiff and light and twitchy now. Do you think taking some oil out would help? Next bike will have adjustable suspension!
Yes, I reduced the oil in mine over time, (and oil viscosity), and it will make it less harsh. Standard air gap and 10wt oil is horrible in my mind, 5wt oil and a bigger air gap/less oil = plusher ride without compromising handling. People will spout on about sag figures, it's worth taking note they're important to getting the bike feeling right.
 

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.... Do you think taking some oil out would help?.....
Don't forget that the air gap only comes into play at the end of the stroke, i.e. when the fork is fully compressed so it isn't the cure you are looking for. As ziplex has said, the sag setting is important, do you know what yours is?
 

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Yes, I reduced the oil in mine over time, (and oil viscosity), and it will make it less harsh. Standard air gap and 10wt oil is horrible in my mind, 5wt oil and a bigger air gap/less oil = plusher ride without compromising handling. People will spout on about sag figures, it's worth taking note they're important to getting the bike feeling right.
I'll be getting my forks serviced soon, bought Hyperpro 10 N/mm linears and got their 7.5 oil in the pack - what's the consensus about the air gap? Bigger air gap that factory 154mm? I've seen people putting Hyperpro springs on the Bird with the 7.5 oil on 140mm gap and claim it works fine.
 

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I'll be getting my forks serviced soon, bought Hyperpro 10 N/mm linears and got their 7.5 oil in the pack - what's the consensus about the air gap? Bigger air gap that factory 154mm? I've seen people putting Hyperpro springs on the Bird with the 7.5 oil on 140mm gap and claim it works fine.
There are two air gaps quoted from the factory
CARB bikes are 154mm
Fi bikes are 142mm

Many of the suspension companies seem to go with the 142mm in all BB forks.
 

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Before I send the bike in the garage, would you guys advise to change the springs on the front while keeping the rear shock? It's probably worn out, given that it's OEM...so new, stiffer front with sponge back doesn't sound right to me.
 

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-Tom- it is always best to do both ends at the same time when making improvements. That said a spring change on the front might not make that much of a difference.
Have you tried a 'bump test' on the rear to check the condition of the shock?
Stand bike upright (helper useful) press down hard and fast and release ….. the back end will come back up (spring pressure) and the bike will 'settle' if you see one 'setting bounce' then good the shock has damping. 2 bounces then the shock is getting tired. 3 then the shock is dead!
 

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My front end improved (both ride and handling) with new springs and lighter oil/bigger air gap but to be honest, the difference a decent shock makes is vast. Having said that I've found out first hand that having the correct spring rate on the shock is paramount. I was over 17 stone and a 1200lb spring suited me perfectly albeit with zero pre-load added...after losing near to 4 stone that very same spring was nigh on useless being as there wasn't enough heft to compress it, I now have a 1050lb spring fitted. I'm fairly sure the standard Showa shock was fitted with a 940lb spring so unless you're a lightweight it's a compromise at the very least. I can assure you a decent quality, correctly sprung shock will transform your bike both in ride quality and handling.
 

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-Stand bike upright (helper useful) press down hard and fast and release ….. the back end will come back up (spring pressure) and the bike will 'settle' if you see one 'setting bounce' then good the shock has damping. 2 bounces then the shock is getting tired. 3 then the shock is dead!
I owe you not one but two and more pints for all the selfless help you gave this uneducated plonker :D hopefully you'll do one more tour de Europe so we can cross paths, thanks for this I'll try it tomorrow.

BUT - I do have to say, perhaps I'm guesstimating too much on the rear shock situation, and it might as well be working well even after 50 years, might be - but it's still "calibrated" for Japanese rider, and I'm 100kg and I don't know what to do to get on their avg weight other than drugs lol :DDDD
 

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.....
BUT - I do have to say, perhaps I'm guesstimating too much on the rear shock situation, and it might as well be working well even after 50 years, might be - but it's still "calibrated" for Japanese rider, and I'm 100kg and I don't know what to do to get on their avg weight other than drugs lol :DDDD
Another easy check (helper or two needed)

Stand bike upright and measure from the centre of the spindle to a point directly above (I put a piece of masking tape on the bottom of the tail piece and put a mark on it)
Climb onto the bike and sit in normal riding position (feet off the ground or if you don't have 2 helpers try not to take any weight through the supporting foot) …. take the same measurement to the same mark.

Take measurement 2 from 1 and see what you have. Anything greater than 30mm and the spring is too weak for you or is very 'tired'. (25mm is about the limit)

(this test assumes the spring is the same one that came out of the factory)
 
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-Tom- it is always best to do both ends at the same time when making improvements. That said a spring change on the front might not make that much of a difference.
Have you tried a 'bump test' on the rear to check the condition of the shock?
Stand bike upright (helper useful) press down hard and fast and release ….. the back end will come back up (spring pressure) and the bike will 'settle' if you see one 'setting bounce' then good the shock has damping. 2 bounces then the shock is getting tired. 3 then the shock is dead!
Along with the above watch the front and back and see if they both come up about the same. If they don't then take note and adjust damping accordingly. You can only adjust the rear on the stock BB. The idea here is to balance out both ends to keep the bucking effect you can get if one end is stiffer than the other.
 

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Quite normal -Tom-, one side of a groove always wears faster than the other and depending on how you ride the actual wear will show up differently.

When tyres don't suit a bike (or how it is ridden) this difference in wear becomes pronounced (you end up with a large step between one side of a groove and the other) and this makes the ride/handling horrible. I suffered this terribly when I fitted Michelin PR4's and binned them well before they were worn out …….. others love them!
 

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Quite normal -Tom-, one side of a groove always wears faster than the other and depending on how you ride the actual wear will show up differently.

When tyres don't suit a bike (or how it is ridden) this difference in wear becomes pronounced (you end up with a large step between one side of a groove and the other) and this makes the ride/handling horrible. I suffered this terribly when I fitted Michelin PR4's and binned them well before they were worn out …….. others love them!
Yeah I regularly got that from my PR2's as well as cold tearing but she still gripped well, I could power slide her if needed and they wore OK so it wasn't an issue ;)
Don't seem to be getting it anymore, not sure whether it's the PR4's or the new Wilbers shock :idunno:
 

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I can't say I'm 100% but I'm pretty sure these tears on the "low" edges of treads weren't there earlier...i noticed it yesterday, thought it was something with my old suspension :D
 

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I can't say I'm 100% but I'm pretty sure these tears on the "low" edges of treads weren't there earlier...i noticed it yesterday, thought it was something with my old suspension :D
Old suspension never helps and can contribute to bad/irregular tyre wear. The point I was making was that the wear you are seeing is 'normal' we all see similar with the variants that we see being tyre design, how the bike is ridden, suspension, road surfaces, road camber the list is endless.
 
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