Moin lieber Leute,

Ich schreibe weiter auf English, weil mir das einfacher ist. Antworter auf Deutsch ist voll prima :)

I have a lovely TR1, which I have modified, in fact backdated, over the last decade:



For more background:
https://www.tr1.de/pages/forum.php?iQuery=num=1310336849;start=all

Now I'm revising the entire front end and after reading the positive experiences with progressive springs, I decided to go for Wirth springs.
Before putting it all back together I have a few questions for the more experienced progressive-drivers around:

I read about good experiences with 12,5 oil (mixing 10 and 15 50/50%)
I read about good experience with welding the two upper holes in the fork-piston

But, what is advisable: doing both at once, or either of the two options? I imagine these measures have more or less the same effect. Don't want to over do it. I'm a relaxed tour driver, 75kg, no sporty stuff required, rarely a passenger.

(yes, I can try, but that requires building twice, which costs more time than asking advice in advance ;)

and secondly: For both drivability and looks I lowered the innerrods 15mm through the tripletree in the past.
I guess with the stiffer wirth suspension I will end up with a higher front end, wanting to lower it even more. I can stick it through even more, but I dislike the look of the forklegs sticking out on top. Has anybody tried to shorten the fork by chopping the wirth springs and compensating with a bush under the small spring, or by just adding the bush and giving the Wirth spring more pre-load?

(also here: yes I can try what effects this has, and how the modified negative suspension travel behaves, but with limited time I beter first ask :) )

Hi I no longer use TR1 forks (switched over to XS1100 forks a long while ago), but the Wirth springs come with oil recommendations and they were (at least back then) a fairly good starting point. I tackled the handling situation by installing a longer rear shock. First from a XT600, currently a KTM Duke 790. Though I may VERY quickly add that buying an off the shelf 390mm long (i.e. stock +25mm) shock, which is available from various resellers might be the much smarter idea, unless you enjoy doing a lot of lathe-work to make OEM-shocks fit.

Hope this helps
Greg

If you close the holes by welding you have to drill them open again with a smaller diameter. I have never done that. Here is what i am using: Wirth springs, 290 ccm hydraulic oil HLP46 per fork leg, lowered the front 20mm.

I would not shorten the spring, the fork travel will be shorter then. If you have a lathe you can probably shorten the inner tube _and_ the spring...