Stock shim stacks for the Marzocchi Shiver 48 on 4Ts

[GMP]

Leon,

That's great. I think you will find a turn less PFP will dial you in for slower technical rocks. It's a real good performing fork.

[Darkside]

GMP, Did you get your forks back from racetech? I'm curious how they turned out

[GMP]

Not yet. To be honest I have limited confidence. If things don't work out I may end up parking it until I can swing a fork swap. Depends on how the fit is and if its acceptably smooth. FWIW, that stock coating is crap. I buffed up as much of the damage as I could before sending them out. Rigged up a paint roller on a rod chucked in a drill, with some aluminum polish, not aggressive stuff. The amount of red that came out was shocking. They should skip the DLC on the lowers, which is little more than bling anyway as the seals do more for that, and T3 coat the internals. Extra process and masking if they want a red color outer.

[Leon_RR250]

Hi!

Finally I tested the fork in our local very technical trail. It is the perfect place for 2T advertisement. We were 9 guys and I was the only one on a 4T. Very thin layer of snow, -5 C, and everything frozen with all the stones and big rocks uncovered. It is like a 40 kms rock garden with several short whooped out transfers. Also 3 different hills of of pure rock with technical step ups and downs. I think the fork is very close for me. My mistake was that I was too eager to start testing comp clickers and PFP. After only the first 4 km to the first break point I opened up 2 clicks (22 out) the comp and 1/4 of a turn on the PFP (started with the stock 2 turns in). The fork was stiff but actually in a very good way until then. The Mitas C17 (the best winter enduro tire currently) with the normal long enduro spikes it just needs a bit more snow and there was no grip on the stones (the same noticed by another guy on a stock EXC300 2013 2T with the same tire). This confused me and I started too early trying out different settings. Until the next break i did not like this change and then I closed back the 2 clicks on the comp and moved to 1 turn in on the PFP. This was better than the previous setting on the slower parts with 2nd gear but too active with some spikes to the hands (blowing through the stroke too easily?) on the other parts. Since I had a small fight/competition with the others also, I decided to stop there with the adjustments and concentrate more on the driving part since the fork was not bad.

Next ride will probably be in the same forest on Thursday with helmet lights and then on Saturday there is another club race in a forest I don't know with some faster sandy trail but also with slower rocky parts. I will just put back everything to stock and start over. And be more patient before trying different settings. It could be that I could even stiffen up things a bit since I weigh 94 kg fully geared, and I am not slow, at least.

Leon

[GMP]

Cold, friction spikes, and snow have to put you out of the norm somewhat and make setup a bit tricky. Most productive setup sessions are riding with that intent only over the same obstacles. A buddy taking some video is good too.

While waiting for my uppers to be done I decided to tear down my compression assemblies completely. Well worth doing as the PFP adjuster orings were dry and one likely would have been damaged soon as it was sticking. A little tricky with some very fine threads in the cap ID, circlip that also retains detention spring, and another circlip on the PFP shaft that sets shaft length which affects PFP preload and comp adjuster range. I cleaned everything up and reassembled with a light synthetic grease. Wow, what a difference! I can now wind the PFP adjuster with my bare had a couple turns just holding the cap in my other hand, and using a 22mm socket also in hand only, a lot more. It should be MUCH smoother to adjust now when assembled and under the min 7mm preload.

Having seen every detail of this fork, it would be a good idea to completely strip, inspect, and reassemble it as part of a new bike prep. Replace anything suspect like a tweaked bushing and lube properly. Might save you a lot of problems.

[Leon_RR250]

Yes, I think even with the same Metzeler tire with spikes it would still be a different story for correct testing and comparison. Frozen ground with all the holes and ruts frozen hard, ice on the rock surface, etc, make comparison to summer conditions impossible. I just was lucky enough to not have real winter until lately so I could understand and solve the major issues with the fork. I will try to find a good compromise setting during the next rides and then just focus on the driving part.

Thanks again for the help! The fork has been ridden 4 hrs after the last service/stack update. I will check the compression system and PFP at 15 hrs, after 11 hrs about. And it will be very easy to update the comp stack based on what I observe during these next 11 hrs. I will keep posting here after every practice.

Leon

[GMP]

Be careful when doing so, very fine threads on the adjuster collar and cap ID. Mine were greased good but orings dry. Should have taken pics but I would have had a very greasy phone. I should get an old shop cam or one of the kids cracked iPods for pics of this stuff.

Uppers are on their way back, suspense is killing me.

[Leon_RR250]

Hi!

We had a night time practice yesterday in the same technical trail as on last Saturday. I started with stock settings (20 clicks out on comp-reb, 2 turns in for the PFP - plus one turn in compared to the end of the previous practice). Same amount of snow, -10C. The fork tracked straight with minimum deflection on the rocks (due to the spikes mainly...). I was confident all the time on what will happen next. It stayed higher and it could absorb the trail junk better. Also more progressive during hard braking. I am also a bit more used now to the long spikes drifting on the rocks. I really like how the fork works now and I don't see a reason to modify the stacks. And I have plenty of room to stiffen it up with clicks and the PFP for soft sand later. The speeds were almost the same as during day time because of the HID lighting, and I think I drove better through the rocks because the fork was so much better. They promised more snow for today and tomorrow so things can be even better soon.

Leon

[GMP]

Leon,

Sounds good! I think the trick is valve it light for technical rocks with a PFP of 0 - 1 turn, and add PFP for the bigger stuff. The thing is the upper range of PFP is useless, your always working in the 0 - 3 range. I've talked to people about softer PFP springs, and its been done, but I do not think its needed as the small bump response is excellent. PFP spring length could be changed so that you can use more of the adjustment range effectively though. The 300 is close stock, I'm still kicking a couple stack changes around but they will be minor. More concerned about the fork tube fit/surface/stiction and its effect on small bump compliance/deflection.

A bit off topic, do you trash your friction spikes on the rocks? I have held off on spikes for winter as my local terrain is a rock pile of a mountain, all size rocks from big slabs, ledges to baseballs but most imbedded. Some of the big stuff on the initial climb gets ice covered from refrozen runoff. Snow is inconsistant and cover always spotty, so you can count on spike/rock contact on a regular basis. Some guys here have them but it seems the use window is very small, as its unlikely to get the right amount of snow for good cover without it being too deep.

[Leon_RR250]

Hi!

Sorry for the delayed answer. I had another practice yesterday with 5 cm more snow but still we are far away from driving in one deep snow rut. Now it was in whoops and frozen sand base with scattered stones in several places. I liked again the fork. Exactly the same settings as before.

For your tire question. This is the same stuff we have in our local technical forest. Rocks eat spikes in general but with the correct rubber the knobs with the spikes wont brake down. Mitas with the white stripe ("winter friction" label) are the best and longest lasting because of the special rubber. And they have a normal and light carcass, nothing like the awfully heavy and stiff Trelleborgs of the near past. I could have used another tire with shorter spikes and spikes on every other knob at the edges for these conditions with minimum snow and ice but I want to save it for a future extreme race. It performed well at the beginning of last December in this race in frozen ground without snow. Now it would be dead within 3 weeks. It's a Cheng Shin 755. Tall and stiff carcass but very gummy very soft knobs. This is the 3rd winter on the Mitas and it is still like new, or at least all the spikes are still present. For you there a good quality tire with the shorter style spikes and a spike on every other side knob would be the best. Here, the Pirelli MT16 has been used for this job but it starts to loose side knobs after some time. The same for the Metzeler Unicross. That is why I feel it is is better to invest in a tire with rubber specific for cold winter, like the Mitas.

Leon