Suspension Options? 1999 CBR600F4

pugheaven

pugheaven

pugheaven

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Well, the "ERIC" went off to get the suspension overhauled after having it looked at at a recent track day on Saturday... I was thinking now I'm getting pretty rapid, that it's all just too soft and sloppy and dips wayyy too much under hard front braking... however the suspension guys conclusion was:


  1. The fork oil is original (1999) and as such is rubbish and barely even oil anymore... (I've not changed anything on the forks, I bought bike 2 years ago on 8,300 miles and it was soft then, and previous owner never changed it... it's now on 22k miles)
  2. Couldn't adjust the front forks due to this, no matter what he did, basically he reckons it's all just blocked and needs refreshing hence adjustment made zero difference... bouncy as hell (I watched him do this and can vouch for it)
  3. Tried to adjust rear, no gas so everything is relying on the rear spring...

So, over this weekend/next week the guys will do all the usual and give everything an overhaul.

However, the bike has 22k miles on it... so, question is, is it worth changing the springs in the front forks and the rear spring, or will they be fine? How long these parts normally last for?

Plus, if I replace these while all suspension is being looked at, would upgrading the springs be noticeable on such a bike? Any advice?

Also, I'm planning on a lot more track days as well as road biking... got one coming up on 12th August again.... however just not sure what make of springs to go for or just go OEM... I know nothing on bike suspension :-(

Any help here guys? So, do I replace all springs with aftermarket and if so, what will give the best adjustment range and quality without breaking the bank?
 
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at 22k I wouldn't worry about the springs

I changed the oil myself in the front forks and that was on a 98 bike with 55k on it not changed since new,it was cloudy and had water droplets or condensation in the fork tubes at the top

you should be able to adjust all the pre load/compression/rebound and feel it stiffen up,i can on my zx6r

I think new oil will help a lot and a re gas of the rear shock
 
Yeah only replace the springs if they are the wrong strength, should be able to find the stock spring strength and find out what's recommended for your weight and riding style.
 
Springs don't really wear out, though they can sag a bit over time. Unless you are particularly heavy or light then I wouldn't bother, especially if you are sticking with the original shock and forks.

Damping is a different matter entirely, and most bikes of the era were sadly lacking from the factory, let alone 15 years later on the original oil. If you enjoy using the bike on the track I would strongly consider a performance rear shock and uprated fork internals.
 
Ok cheers guys so looks like springs should be cool, just some TLC anywhere else...

I'm tempted to buy new uprated but always concious that this was always going to be a cheap hobby hahaha
 
With your standard springs you can try and get the front preload sag set up - usually helps to use a cable tie round the fork legs to give you a measurement point. From memory you want the front end to sit 20mm so you'd sit the bike on it's wheels, put the cable tie to the top of the fork dust seal then lift the weight off the front suspension and you'll expose more fork leg. This should be 20mm different. Or you can do similar measuring from top of fork bottoms to the bottom yoke. Tipping bike over while on sidestand is one way to get the weight off the front end.

For the spring rate this is something that will have a ball-park figure for what's best for track use, this will depend on rider weight. If you keep at the track stuff, once your riding style settles down you may find that the spring rate isn't ideal for you. All depends on how you prefer the feel of the front end under braking and how far off maximum travel you are at this point.

The springs mainly control the large movements like forks diving under braking. If they're too soft you can try raising preload and compression damping but both these cause drawbacks - running wider in corners and lot more choppy over bumps. If you go for uprated springs but with standard damping you can also get less control at the front end as the damping can't control the spring movement effectively.

Best long term fix is a fork conversion from a specialist like Maxton, just depends how serious you want to get and how much you plan on spending. Second hand kit off another track bike could be an avenue to go down. I got a set of Maxton track forks for an R6 for £50 plus my forks as they were off a bike going back into road trim. That's when I also found that one set of springs for a heavier rider than myself were actually too soft for me and went through the cycle of winding up preload and damping before chatting with Maxton and getting the springs swapped.

Hope that helps without over-complicating things :)
 
tl45 said:
The springs mainly control the large movements like forks diving under braking.
Click to expand...

Low speed compression damping is what controls forks diving under braking. Stiffer springs may result in less total dive for any given braking, but it's the damping that determines how well controlled it is.
 
I don't think the OP has the option to adjust low speed compression damping?

Maybe newer spec kit can give the benefit of more control & adjustment through damping without having to go heavier on the springs but I never had that option available on any of my bikes.

Last bike I had suspension experience with being an 05 600RR which I built as a track bike pretty much from new, suspension being one of the first things I got sorted - I ended up swapping to springs heavier than Maxton's usual spec, to get the amount of dive and behaviour under braking to my liking.
 
A lot of bikes are interchangeable. A bit of research (you need distance between top and bottom holes and stroke length) might see you be able to ebay/whatever forum you get donor off another shock that bolts right on. Kawasaki shocks are popular for swaps with Suzuki owners, for example.

Not much info out there about shock changes at first glance. Seems Honda owners just want to stick to Honda stuff.
 
Most bikes the excepted static sag is around the 35mm front n rear
some good video's to watch on youtube, search for dave moss and look at his vids called 2 clicks out


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Cheers guys, appreciated replies... at the moment, track days aren't serious but I can see myself going more and more that way as I love speed and the through of technically getting more and more out of the bike... I can see me keeping this CBR for track and picking up my only other love (2010 Orange Blade) as the road bike... tough one... as at moment, I'm caught 50/50... and just know my suspension can be better setup, it's basically all too soft... will see how it goes when I get it back this week as next track day is Tuesday... so, lets see what difference it makes.
 
Well decided to stick with original springs and them to jutndo a full service on all suspension. Even they admitted that although nice to have uprated springs, you'd be hard pushed to notice on this bike for the use I give it... So just a service. Will see how this let's me alter settings etc and take it from there. Track dayntuesday get bike back Monday
 
Well, got bike back, forks had new seals, fully cleaned, new oil blah blah and they were superb (althought felt weird at first) on Tuesday's Trackday at Oulton Park. However, I'm going to replace the rear damper with one of these... anyone have any opinions or have used either?

Nitron
http://www.intobikes.co.uk/products...k-Absorber-suitable-for-Honda-CBR600-F-X-1999


  • 2-way combined damping control
  • 40mm damper piston
  • 14mm piston rod
  • Adjustable spring preload
  • Independent adjustable ride height
  • Hydraulic preload option
  • No remote canister
  • 24 click combined adjustment
  • Complete with Nitron spring
0d7d34cb-spacer.gif

d1f3249b-sport_3.jpg


or...

Hagon

http://www.hagon-shocks.co.uk/catalog/partdetail.aspx?partno=M61054


  • Mono Shock,
  • 38mm gold zinc plated steel damper unit fully re-buildable,
  • 18mm piston rod, wide ranging single circuit progressive damping adjustment with automatic compression / rebound balance.
  • Red powder coated spring, fully progressive spring pre-load adjustment.
  • Supplied complete with end mounting bushes / bearings, tools and instructions for spring and damping adjustments. 2-year guarantee.

MONO.jpg
 
pugheaven said:
Well, got bike back, forks had new seals, fully cleaned, new oil blah blah and they were superb (althought felt weird at first) on Tuesday's Trackday at Oulton Park. However, I'm going to replace the rear damper with one of these... anyone have any opinions or have used either?

Nitron
http://www.intobikes.co.uk/products/...BR600-F-X-1999

2-way combined damping control40mm damper piston14mm piston rodAdjustable spring preloadIndependent adjustable ride heightHydraulic preload optionNo remote canister24 click combined adjustmentComplete with Nitron spring IMAGE#1
IMAGE#2

or...

Hagon

http://www.hagon-shocks.co.uk/catalo...?partno=M61054

Mono Shock,38mm gold zinc plated steel damper unit fully re-buildable,18mm piston rod, wide ranging single circuit progressive damping adjustment with automatic compression / rebound balance.Red powder coated spring, fully progressive spring pre-load adjustment.Supplied complete with end mounting bushes / bearings, tools and instructions for spring and damping adjustments. 2-year guarantee.
IMAGE#3
Click to expand...

I have a Nitron on my bike, it's transformed the handling


Posted from Overclockers.co.uk App for Android
 
i was gonna say i don't think they can re gas the original shock which is a shame tbh,see loads of em on ebay
 
pugheaven said:
Well, got bike back, forks had new seals, fully cleaned, new oil blah blah and they were superb (althought felt weird at first) on Tuesday's Trackday at Oulton Park. However, I'm going to replace the rear damper with one of these... anyone have any opinions or have used either?
Click to expand...

Nitron every single time. The Hagon is an emulsion shock, the gas and oil mix together to form a emulsion during operation which isn't ideal for damping. Better than a worn out OEM, and fine for average road use but it's not a high performance system.

The Nitron is a proper monotube gas shock that separates the oil and gas with a floating piston, far better for performance damping.
 
wazza300 said:
i was gonna say i don't think they can re gas the original shock which is a shame tbh,see loads of em on ebay
Click to expand...

You can get the OEM shocks rebuilt but it's pointless just re-gassing them, it won't make any difference to the damping. You can get a Gold valve kit which will improve it, but the total cost of the kit + fitting is probably as much as a basic Nitron.
 
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