Date: 23-04-24  Time: 20:21 pm

Author Topic: Front fork refurb/rebuild: Situation & options.  (Read 8551 times)

b1k3rdude

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Front fork refurb/rebuild: Situation & options.
« on: 19 May 2016, 08:56:05 pm »
The bike is a 2005 gen1 with 20k on the clock, I already have Devilsyam R6 shock but never knew how bad the front was untill upgraded my work bike to a K6 Bandit 1200. This quote sums it up -

"The big problem is the forks do not have enough rebound damping, which makes the forks spring back very quickly when you let go of the brake or accelerate, this causes the bike to run wide out of corners and makes the bike difficult to turn in to a corner. The forks also have too much compression damping which makes the bike kick off small bumps in the road. This problem can make the ride uncomfortable. We modify the forks fitting harder springs to suit the type of riding you do and also your rider weight, we also re-valve the cartridges increasing the rebound damping and reducing the compression damping"

I have tried every setting from stock to softest and nothing worked, I still ran wide and got kick off from the road surface, so -
  • ktech - probably the best but also the most expensive and at 5th the cost of the bike value Im on the fence...
  • Maxton - presumably not quite as good as ktech? but then I assume cheaper?.
  • Brooks own - they offer to a refurb service, where they do a similar job to maxton but at at a lower cost.
I already have a set of K-tech 9.5nm springs in the forks, but the stock damping is I'm guessing nullifying any benefit - coz I was unable to discern any real difference.
All I need is for the suspension to be at least as good as the Bandit's, from a ride quality point of view and without breaking the bank. From the brief chat I have with brooks their full monty refurb service, I believe they will replace a bunch of the damping components with custom parts? So has anyone gone down this route and whats the verdict?





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Re: Front fork refurb/rebuild: Situation & options.
« Reply #1 on: 19 May 2016, 09:47:25 pm »
Not used Brooks but revalving is definitely worth doing, if done properly.  I actually think Maxton do a slightly more thorough job than K-tech because they replace the OE damper tube - which is alloy and wears quickly - with a steel tube.  K-tech might do that but they didn't used to advertise the fact.

I will say that having ridden several versions of fork mods, I was pleasantly surprised by the Hyperpro progressive spring option.  They use different spring rates to the stock Yamaha springs and even with stock valving, the ride quality was improved.  Worth a punt if you're watching the budget.

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #2 on: 19 May 2016, 09:55:29 pm »
Give the guys at www.tyres4bikes.co.uk a call. Ask for Stef and say Peasy sent you. He'll talk you through some options. He did my gen 1 forks after I fitted the r6 upgrade and I'm more than happy with my set up, not changed it or even thought about changing it since.

b1k3rdude

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #3 on: 19 May 2016, 11:11:35 pm »
@Falcon, I think I will email bcc ktech, Maxton, Brooks just to see what they do and what they replace.

@Peasy, Will do that grand.

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #4 on: 21 May 2016, 12:20:14 pm »
Give the guys at www.tyres4bikes.co.uk a call. Ask for Stef and say Peasy sent you. He'll talk you through some options. He did my gen 1 forks after I fitted the r6 upgrade and I'm more than happy with my set up, not changed it or even thought about changing it since.

Afternoon

Spoke to Stef, and its by far the cheapest option. Where are you located, anyway close to hertfordshire..?

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #5 on: 21 May 2016, 03:11:08 pm »
I have done the Hyperpro mod and set up following there guide for settings, I am very pleased with the way the bike handles. For me it was the best way to go for the price, 116 for the springs and 60 to fit which included fitting new seals. I have not been on a bike with the full  revalve so can not compere but  just how far can you go and at what price is  it worth? For me I think there is a limit to just how much you can spend on a bike designed nearly 20 years ago. Every one has a opinion of what that price is but for me on my budget the revalve  is a step to far, and I wonder if a rider like me with not a lot off skill  and  limited bravery would tell the difference any way. I have read here many times that the biggest difference to the handling is the rear shock, so that is where my next money will go.

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #6 on: 21 May 2016, 05:02:40 pm »
Give the guys at www.tyres4bikes.co.uk a call. Ask for Stef and say Peasy sent you. He'll talk you through some options. He did my gen 1 forks after I fitted the r6 upgrade and I'm more than happy with my set up, not changed it or even thought about changing it since.

Afternoon

Spoke to Stef, and its by far the cheapest option. Where are you located, anyway close to hertfordshire..?



Good stuff. I'm up in Lincolnshire mate I'm afraid.

b1k3rdude

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #7 on: 21 May 2016, 10:51:29 pm »
@Ricky, but two biggest issues with the front are the kick-back of the road surface drifting wide in corners. Both of whcih the bandit is noticably better at, so if I simple refurb/service can bring the fazer to the same level as the bandit  - it will make me a happy camper.

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #8 on: 21 May 2016, 11:00:36 pm »
Alpha suspensions in Morley is worth a shout mate, very well know around my neck of the woods!!!

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #9 on: 22 May 2016, 10:26:43 am »
Spoke to Stef, and its by far the cheapest option.....
If I were in your position I would find someone local that could help you check your preload and damping settings just to make sure you have these optimally set up. With my new 10.0 K-Tech springs I found they were a bit too harsh with the recommended 35mm sag so I slackened off the preload and used a cable tie to check that in normal use I still have 10-15mm spare travel which has helped. With stronger springs you also need to increase the rebound damping from stock settings and this should help with the 'kick-off' you mention, increasing compression damping may help with running wide.

If you're happy that you've tried all of this but still need to do something with the suspension then as you've already had new springs and oil which hasn't sorted the problem as far as I can see the only options left are to either replace the fork internals or do the R1 fork mod neither of which will leave you much change from £500. So if you're getting much cheaper quotes I would make sure that you are not just paying to have new springs and oil again ..............


« Last Edit: 22 May 2016, 10:28:35 am by PieEater »

b1k3rdude

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #10 on: 23 May 2016, 01:03:17 pm »
Alpha suspensions in Morley is worth a shout mate,
Will give them a call.
  • If I were in your position I would find someone local that could help you check your preload and damping settings just to make sure you have these optimally set up.
  • With stronger springs you also need to increase the rebound damping from stock settings and this should help with the 'kick-off' you mention, increasing compression damping may help with running wide.
  • If you're happy that you've tried all of this but still need to do something with the suspension then as you've already had new springs and oil which hasn't sorted the problem as far as I can see.
  • So if you're getting much cheaper quotes I would make sure that you are not just paying to have new springs and oil again.
  • I will do some research, but ideally Im guessing I would want someone who has had exp. with FZS1000's.
  • I tried max & min comp and rebound damping and all that I could notice was the kickback remained unchanged, but with both set of damping set to min the forks dived more.
  • Would you agree that the above would indicated that something isnt right..? - The issue is I havent got another FZS1000 or FZS1000 forks to compare - just my bandit 1200.
  • Yeah, I really really want to avoid spending money and then have the front behave the same. I already have a set of brand new springs so I will paying for the internals to be serviced.
Do you or anyone know what weight the stock spring are? as a comparison to the 9.5 ktech that are in there atm
« Last Edit: 23 May 2016, 01:04:06 pm by b1k3rdude »

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #11 on: 23 May 2016, 01:52:56 pm »
Sounds like you've truly had a good go with the damping and preload and haven't been able to find a setting that works so it would just be getting a second opinion from someone that knows about suspension, not necessarily about the Fazer, but do give a bit more rebound damping another go just in case. Where abouts are you based maybe you could meet up with another Foccer to compare notes? Some folks like me don't seem to have too much of a problem with the forks after having new springs / bushes / oil & seals, or are at least happy enough with their performance, but others like yourself don't seem to be happy with them at all. I don't know whether some Fazer forks are better than others or some folks haven't had recent experience of decent modern forks to know the difference between 'OK' and 'good', which I'm happy to admit may be the case with me as I've not really ridden anything other than my Fazer for the past 7 years, although I've previously owned sports bikes with USD forks. Just to reiterate I'd be careful about having the 'internals serviced' without knowing exactly what this consists of, if you want anything to change noticeably you'll want them replaced with aftermarket parts like the K-Tech kit rather than the OEM kit cleaned up and refitted with new bushes.

According to this thread the OEM progressive springs are 8.0 at the top end and 12.5 at the bottom - http://foc-u.co.uk/index.php/topic,3598.msg29436.html#msg29436 - I guess you could try Hyperpro progressives to see if they are less prone to kick back on you. I'm not overly enamoured with their suggested settings though which is to run without any compression damping, I'd have though that compression control would be more important with progressive springs than linear.....

b1k3rdude

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #12 on: 23 May 2016, 10:42:29 pm »
  • Where abouts are you based maybe you could meet up with another Foccer to compare notes?
  • Just to reiterate I'd be careful about having the 'internals serviced' without knowing exactly what this consists of, if you want anything to change noticeably you'll want them replaced with aftermarket parts like the K-Tech kit rather than the OEM kit cleaned up and refitted with new bushes.
  • According to this thread the OEM progressive springs are 8.0 at the top end and 12.5 at the bottom - http://foc-u.co.uk/index.php/topic,3598.msg29436.html#msg29436

  • South Herts, j20, M25.
  • Well Maxton have been the most clear about what they do, dampper catridge tube, piston valve/ring, compression adjuster. Im waiting for that Shope Peasy mention to get back to me.
  • So it sounds like my 9.5 ktech linear spring should suite nicely.

b1k3rdude

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #13 on: 25 May 2016, 02:29:56 pm »
Just following on from this as I still exploring all avenues....

Spoke to Yamaha Tech UK and they are saying completely the opposite to Tyres4bikes, Brooke,m Maxton, ketech, etc etc.. They have said all I need to do is have the right weight oil in there and the steps would be -

1. Drain the oil out of forks and leave to drain for a few hours.
2. Flush the forks with cheap 5w oil, and again leave to drain.
3. Then place correct amount of Kayaba 01 (from what I have found online this is 5w oil)

Then set the forks back to std setting (if not already) and work work from there.

Yamaha and Tyres4bikes have never heard of the cartridge tube wear, as per Maxton's statement. And as these replacement Stainless Steel tubes cost £100 plus vat per pair I am leaning away from going with them (Ktech was out of the window ages ago due to the new ludicrous price PDQ quoting @£750 fitted).

So now I am at the stage where I am strongly considering Tyres4bikes, as for £180 they will
  • dissemble and clean all the internals.
  • change the oil and dust seals.
  • replace the fork oil with 7.5w.
  • return postage.
@Peasy, can you give me a break down of what your bike was like before and after please?

« Last Edit: 25 May 2016, 03:17:14 pm by b1k3rdude »

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #14 on: 25 May 2016, 10:50:20 pm »
FWIW, the problem lies in the compression damping valves.  They are simply too crude to allow decent high speed compression damping, which is what determines the ride quality.  Low speed compression damping is what controls dive on braking - in basic terms - but high speed damping determines how the forks respond to rapid transient movement such as you find when hitting the usual bumps and so on in the road.

You can improve high speed damping response a little by using lighter weight fork oil (Silkolene RSF 2.5w worked for me) but the trade off is a reduction in rebound damping. 

Frankly, you can do what Tyres4bikes are offering yourself at a considerably lower price.  Unless you make some fundamental changes to the valving, anything else on offer will be a compromise. 

Yamaha are trying to make light of the fact that the stock forks are cheap and nasty.  If it was simply a case of the right oil and air gap, how come Yamaha never sent the bikes out of the factory that way?

Your call but IMHO there's no cheap solution to this and anyone telling you otherwise is only selling you a band-aid.

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #15 on: 26 May 2016, 07:17:52 pm »
  • The problem lies in the compression damping valves.  They are simply too crude to allow decent high speed compression damping, which is what determines the ride quality.  but high speed damping determines how the forks respond to rapid transient movement such as you find when hitting the usual bumps and so on in the road.
  • but the trade off is a reduction in rebound damping. 
  • Frankly, you can do what Tyres4bikes are offering yourself at a considerably lower price.  Unless you make some fundamental changes to the valving, anything else on offer will be a compromise. 
  • Yamaha are trying to make light of the fact that the stock forks are cheap and nasty.
  • Your call but IMHO there's no cheap solution to this and anyone telling you otherwise is only selling you a band-aid.
  • So in this instance the maxton route would in this context would be the most cost effective route - (Im still not sold on the damping tube wear)
  • As in when I release the brakes the front jumps up faster making me potentially run wider in corners? - I can most likely live with that. Yamaha suggest I get that insanley price kaya (or something) 01 fork oil and from what I could find its either 2.5 or 5W. What weight oil would you recommend to try?
  • Yeah I figured, I just don't have a tool to hold the catridge while I do up the allen bolt at the bottom - does Pats site demonstrate an work around for this..?
  • I'm not entirely surprised by that.
  • I don't mind spending money upto a point, I just want it done right once - I don't want to have to revisit this after the fast.
Its a shame you don't do forks as well Mike, or do you....?!

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #16 on: 26 May 2016, 07:42:56 pm »
I seriously considered the R1 route for quite some time but in the end couldn't justify it mainly due to my type of riding so decided to go down the rebuild and setup route with some flashy diamond black coating on the stantions just to be a bit different.
Russ the mechanic that did the work and set up reckons for most people fresh oil, maybe new springs and the bike suspension setup all round
(R6 rear) does the job. I'm well happy with mine.

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #17 on: 26 May 2016, 08:06:09 pm »
  • Yeah I figured, I just don't have a tool to hold the catridge while I do up the allen bolt at the bottom - does Pats site demonstrate an work around for this..?


Dude - I've rebuilt my forks 4 times. You don't need the tool, or at least I didn't. Before doing anything, whack them in a vice (with soft jaws) and crack the nut off before disassembling the top half. They'll be f. tight, so if you don't have a proper socket set and snug fitting allen bits, get some. Those right angled allen keys that you'll find in the toolkit will be of zero use.


The bushes will be worn out, so get some ahead of time. They wear out really quickly. Also, don't forget to remove the circlip from the oil seal before extracting the stanchion. Like I did once. (embarrassed blush)


b1k3rdude

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #18 on: 26 May 2016, 08:30:08 pm »
Dude - I've rebuilt my forks 4 times. You don't need the tool, or at least I didn't.
Ok, but then how do you stop the cartridge tube from spinning, when doing the allen bolt up?

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #19 on: 26 May 2016, 08:43:09 pm »
Shove a broom pole up the inside :)

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #20 on: 26 May 2016, 08:56:08 pm »
Dude - I've rebuilt my forks 4 times. You don't need the tool, or at least I didn't.
Ok, but then how do you stop the cartridge tube from spinning, when doing the allen bolt up?
I've never had a problem doing the bolt up, it's normally undoing it that's the pain. Top trick is to hacksaw the right angle off a correct size Allen key leaving you the long straight bit then use this in an electric drill, the initial torque of the drill spinning up usually works, i.e. several quick burst after the tube stops spinning, may well work in reverse for doing it back up but if you're refitting all the parts having cleaned everything with paraffin and before putting any oil in the bolt should tighten up without issue. 

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #21 on: 26 May 2016, 09:23:33 pm »
Dude - I've rebuilt my forks 4 times. You don't need the tool, or at least I didn't.
Ok, but then how do you stop the cartridge tube from spinning, when doing the allen bolt up?


Fair question. Thing is, I'm not entirely sure it's even necessary to have the tool.


I know I must sound like I'm talking bollocks, but I've done this four times now, it's just not an issue. If it was spinning, you certainly couldn't torque them up correctly either, but I am talking about a bike that's done 149600 miles, 4 trips up the Alps and passed 14 MOTs with not even an advisory, so I must have done something right! I can't imagine I've just got lucky....


For getting them undone, an impact driver is very handy, by the way. You don't even need a clutch puller to take the flywheel off an engine with one of those. Brrrrr, click, and it's off... simple.


Edit: I probably am talking bollocks.Did I just use a spanner... I honestly can't remember...
« Last Edit: 26 May 2016, 11:08:49 pm by AyJay »

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #22 on: 26 May 2016, 10:30:42 pm »
There's several threads on the FZ1OA site showing cartridge holders owners have made out of plastic tube and the right size socket or box wrench.  Also, if you have access to an air or battery-powered impact driver, those will rattle the allen bolt out effectively.

I'm persuaded by Maxton's view that the alloy damper tube does wear.  A look at old fork oil coming out of several forks shows just how much metal has gone into the oil over time.

Working on forks at the pro level, fitting and calibrating new valves and shim stacks for example, requires tools and workshop facilities most of us don't have.  However, the simple nature of the Fazer 1000 forks makes them a lot easier to work on at the basic level of changing oil, replacing seals and bushes and fitting new springs.

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #23 on: 27 May 2016, 12:14:41 am »
A 26mm socket taped to a length of alloy or plastic tubing about 20" long,drill a hole through the opposite end of the tubing to allow the insertion of a screwdriver forming a  T-bar,works a treat.
Whizz kid sitting pretty on his two wheeled stallion.

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Re: Front fork refurb/rebuild: Situation & options.
« Reply #24 on: 27 May 2016, 04:41:26 pm »
  • [size=78%]I'm persuaded by Maxton's view that the alloy damper tube does wear.  A look at old fork oil coming out of several forks shows just how much metal has gone into the oil over time.[/size]
  • [/size][size=78%]Working on forks at the pro level, fitting and calibrating new valves and shim stacks for example, requires tools and workshop facilities most of us don't have.  [/size]
  • [/size][size=78%]However, the simple nature of the Fazer 1000 forks makes them a lot easier to work on at the basic level of changing oil, replacing seals and bushes and fitting new springs.[/size]
  • I find this encouraging, specially from some that has seen the inside of a lot of forks.
  • If the £365 maxton quoted included that SS catridge tube  then its seriously tempting.
  • Yes, I have thought about that each every time I have broached the idea of an R1 conversion - the fazer forks are going to cheaper to maintain moving forward.