Fork Spring advice

[markycee]

Hi,

I think I need to upgrade my front springs. I weigh 100 kilos and find the standard very weak and they bottom out easily.

Is it worth trying a different oil before I do anything else? Would this make any improvement or difference?

If not, anyone recommend springs? I've seen K-tech for £80 or Hyperpro for £116 with oil etc (on ebay)

Is it an easy job? Do I have to strip much of the bike down and completely remove the forks or can it be done in situ?

Thanks if anyone can help advise

Mark

[gafr]

have been told that the better springs make a lot of difference, havent tried it myself though. with regards to installing them, piece of piss, all done in situ, drain oil, take off top of shock, take out old spring,put in new, add oil and do back up. job done!

[mik_str]

You definitely want to get stiffer springs. The stock units are (IIRC) 0.585 kg/mm, ideal if you weigh 115 lb..... At your weight, you will likely need to get something around 0.95 - 1.0 kg/mm. Have a look at the RaceTech site, they have a rate calculator.

Not sure if they ship to the UK, but Sonic Springs (US) sell good quality springs for a very dcent price ($80 US).

You may want to look at doing the valving (notably the compression) while you have it apart, as the stock set-up has excessive high-speed compression, causing the front end to lock up when called upon to compress quickly.

Good luck

[AMCQ46]

it will make a big difference as the stock springs are too soft so you cant fix it with heavy oil.

if you talk to a good suspension shop they will work out a spring rate for your weight and riding style, or you can look at the racetech website and calculate your own.

you need to take the forks out to empty the oil, but changing the springs is fairly easy to do. remember when you fill with oil spec most people use is 7.5wt oil set to 140mm air gap. and to set the air gap that is with springs removed and the fork fully compressed

[markycee]

Tks. So what is the easiest way to drain oil. Could I use a syringe or something (to avoid removing the forks or hanging the bike upside down!)

[AMCQ46]

take the forks out..........you already need to have the front end off the ground to remove the springs, so it is only a bit more work to remove the front wheel and forks.

if you have an ABBA stand then it is nice and stable to then use a car jack under the sump. if you only have a paddock stand you can still do it, but you need to make sure it is all well positioned to be stable, and perhaps some ballast on the pillion seat to help keep it settled.

also make sure you slacken all the wheel nuts and fork tops before you lift the front, as it saves you unbalancing the bike with its in the air.

BUT dont undo all the yoke clamps or fully remove the fork tops with the bike resting on the front wheel of the front end will collapse

[VTRDark]

There's a nice write up on improving the stock front suspension. I shall be doing this myself shortly. http://www.ablett.jp/bikes/vtr/vtr_sus.htm

But as has been said remove the forks from the the bike. It also gives you the chance to clean up the stanchions and put a coat of paint on the fork lowers if needed.

(:-})

[markycee]

Tks for all tips so far..Convinced I need to do this job, but as usual so many options and I'd hate to make the wrong choice.

I have just been looking at K-tech springs, but they are linear. Anyone got advice on which is best "Linear" or "Progressive"? This is for Road use. Obviously the shop selling the linear ones said that linear is much better, but I guess they would!

[AMCQ46]

I have used both and I think Linear is better, but you need to get the correct ones for your weight.

[VTRDark]

Linear springs will give you the same constant compression throughout the range and are weight related. Progressive are more of an all round spring to suit a range of riders weights and will progressively get more resistance the further the fork travel.

I guess if it's just you riding the bike and you are a more sporty rider then linear would be the way to go. But if you do a lot of touring and sometimes carry a pillion then the Progressive may be the way to go.

(:-})

[Flatline]

Google Brookesuspension, they supply K-Tech

[seb421]

Hi,

I think I need to upgrade my front springs. I weigh 100 kilos and find the standard very weak and they bottom out easily.

Is it worth trying a different oil before I do anything else? Would this make any improvement or difference?

If not, anyone recommend springs? I've seen K-tech for £80 or Hyperpro for £116 with oil etc (on ebay)

Is it an easy job? Do I have to strip much of the bike down and completely remove the forks or can it be done in situ?

Thanks if anyone can help advise

Mark

Spring Rate for front -

16 Stone = 0.938 kg/mm = 9.19 N/mm = 52.52 lb/in

http://www.vtr1000.org/phpBB3/viewtopic ... 73#p232324

[popkat]

Just to add, wind the preload all the way out and use a deep socket to undo the top, this takes some pressure off the spring. Also wind the rebound adjuster screw all the way in then just crack the nut underneath to get the top off of the damper tube and uncrew the top off. turn the nut just a couple of threads down. when you put it back together screw the top back on until it hits resistance then wind the nut back up and tighten.

[markycee]

To follow up on my original post, I'm just about to order Hyperpro progressive springs. I only use the bike on the road (no track stuff unfortunately) and from various searches on the internet they seem to rate well with feedback from people that used em.

I have no idea what oil weight to use. I'm taking a guess 7.5 So unless anyone comes back and says "NO its a bad idea" I will order on Monday ready to do the job at the weekend.

[NHSH]

To follow up on my original post, I'm just about to order Hyperpro progressive springs. I only use the bike on the road (no track stuff unfortunately) and from various searches on the internet they seem to rate well with feedback from people that used em.

I have no idea what oil weight to use. I'm taking a guess 7.5 So unless anyone comes back and says "NO its a bad idea" I will order on Monday ready to do the job at the weekend.

Not sure if you ordered teh spring already..
I don't know if you can get the Race Tech springs from the US, they cost about $100 US Dollars for the pair and I would get the valves as well, if you can order these you can ask for the correct spring for your weight as well, that way your setup will be allot easier from the get go.
good luck, cheers mate