Sprint, uprating the forks

Hi
My bike is a 96 Sprint with no manual rebound or pre load adjustment on the front forks.

Ive read about the forums and found that people are prefering Hagon or Race Tech springs with thicker oil (15wt). I have also read about gold valve emulators which go with the race tech springs.

My bike seems to dive quite a lot when braking (Ime 16 stone) so Ide like to stiffen the front obviously (Ive allready increased the spacers above the springs), but not so much as to make the ride to hard when going over the bumpy stuff so would the race tech springs be to hard?

I have gone on the race tech web site and been recommended for 1.025kg spring rate with the gold valve emulators.

The gold valve emulators, am I right in saying there for the forks rebound damping as I look in my haynes manual and there are no existing valve emulators in the forks in the diagram for my bike, how come?

Are the Hagons and a heavier oil more suited to more all round riding?

Also how do you correctly measure the sag of the bike, where do you take the measurments from?

Any advice would be appriciated
Thanks

[ezride]

I did the front end on mine about 5 years back, and it totally transformed the bike. Best mod I've done by far. Changes:

1. Race Tech Gold Valves

2. Heavier, constant rate springs (.95 kg are perfect for me).

3. I lowered the front (raised the forks in the triple clamps) 1/2" when I put the front end back together.

The stock setup uses very spongy dual rate springs. The initial rate is so low that the slightest tug on the brake sends the front into a nosedive. Now there's very little dive, great control, and the ride is not harsh. I see no comromise made for the stiffer springs/added control. Spring manufacturer should not matter if they are good quality (Traxxion Dynamics in Georgia did mine, and used their own spring supplier).

Front definitely seems to be better controlled in bumps and transitions. I can't really say if that's the gold valves since I changed the springs at the same time. I won't go back though.

Steering is quicker with the lowered front; the bike is more willing to turn, and there doesn't seem to be a stability penalty. Probably not quite as stable as stock, but I've never had any issues. 1/2" made a big difference (said she...).

Ok thanks for the info, looks like Ill be doing a change soon I think.

Hi Lyndon900,
I did the racetech front suspension upgrade on my sprint executive 6 months and 2500kms ago - absolutely transformed the ride and handling. I also did the usual research in an effort to improve the handling - searched the web, read tech articles and talked to motorcycle suspension specialists.
In summary this is what i found out.
Stock springs on these triumphs are suited to a rider of about 70 kgs! These were replaced by racetech springs to suit my weight - 90 kgs - and are non-progressive. Aparently non-progressive springs enable the front suspension to be more accurately setup with respect to damping - both compression and rebound. Also their behaviour is more predictable compared to progressive types.
The original damper system in the front forks is pretty crude - basically a piston with a hole in it immersed in oil! At slow speed it allows relatively lots of oil to flow through which gives these bikes a very soft feel and makes the front end dive under braking. At faster compression speeds such as hitting a bump at high speed the oil 'backs up' as it can't travel fast enough through the damper hole and restricts the forks from compressing making the front end feel harsh.
The racetech system damper system or valve emulator is much more sophisticated and uses reed type discs in a stack to control the oil flow. An advantage of this system is that the 'stack' is tunable by using different discs to control the entire range of fork compression and rebound damping.
In a word the bike now handles like its on rails. Wheras before the front end would wallow around bumpy corners, run wide and feel very unstable.
If all you do is change the fork oil weight you may correct one aspect of the front end behaviour (ie slow speed compression) but make it worse elsewhere.
Its not cheap to upgrade the forks - mine cost about $660 AUD but its excellent value for money and like i said its transformed the bike . The other alternative was to sell it and buy a bike that handled!!

Thanks for the explanation and your advice goosieman

Thanks for the info ezride... I am having the same problem on my Executive. Nothing I can't live with until I have the funds to correct the problems, but I have 25,000 miles on the clock and it is time to do some research. I will check with Traxxion Dynamics as I live in Georgia. Any suggestions for the rear shock?