Coil Conversion for the Pike

Hi everyone – I’ve been following this post a while with interest so thought I’d join up…

Just a quick update in that I contacted Tft about their coil conversion and got the following reply:

“E don’t have a coil conversion kit as yet.

It’s been trail tested for the last year or so and will be released at Sea other on April 20th. We will have inventory and be ready to install the kit then.”

I’ve replied to try and get a few more details on what the conversion will consist of, costs, etc. but I’m assuming I’ll not get much back. If I do I’ll post it up.

How are people getting on with their Crconception conversions? I’m very tempted but worry if the charger damper is going to be effective? Not knowing much about dampers I presume it is set up for a progressive spring rate…

Thanks,

James

The charger damper is a separate issue and in my opinion will work broadly the same with coil or air. Besides, a Pike with no tokens isn’t that progressive really, have a google for some graphs. If you do use tokens then maybe think about why you use them before buying a coil replacement.

Done but only ridden around the garden so far. I have about 22% sag and I hope it’s not just new kit placebo but I am liking the feel. I have converted a dual position Pike and the weight has increased by 150g which I think is very acceptable. First proper outing will be later in the week at Flyup417 (never been but they had a £20 special offer and I got tempted).

Sweet!

Nahh, you’ll have noticed an even bigger difference if you had the DPA model.

Suppose I should wade back in after ride 1 yesterday. Bit sloppy at Innerleithen so not exactly ideal conditions for checking things out but still a couple of definite improvements. Small bump action is certainly better, no seals for my 60kg bulk to fight against. Also noticed that in flat turns and catch-berms I was bracing for the inevitable mid-stroke wallow only to find it never happened. Yet conversely was using a bit more travel when needed as there was no token induced, massive, ramp-up. Seemed like a really good balance, basically what coil setups are known for. The only slight negative was that there is a slight noise from the spring side that is either the spring rubbing on the leg or the base moving up the leg, but it really is the most minor of niggles and I’ll just see if the spring needs seated better or just need to get some more grease involved. Looking at a click or 2 extra LSC, but reckon that’ll be about it and don’t even feel like the tweak is an absolute must

Definitely happy with the improvement so far, looking forward to riding in slight better conditions!

No noise with mine, at least – not any that I notice….. check to see if it’s seated/installed correctly. If it’s the base, maybe a rubber washer between the clip ring and the plastic base would dampen it a bit. A bugger tonne of grease might hold it from rattling, if that is what is happening.

My old coil Lyriks used to make quite a lot of coil noise though.

It’s not the base, definitely a moving part. If I take the stanchion protector (acetate out it should have witness marks on that will make it obvious if it’s spring or the spring seat

Coil bind is endemic in coil forks, shrink wrap or a greased inner tube usually sorts it.

I’m thinking though, could it not be the plastic base plate that holds the negative spring? What’s holding that in place when the fork is compressed? I reckon it could rattle around a little if there’s too little grease on it.

The plastic shrink wrap looks like it may stop it from moving up and down, so perhaps you’ve inserted the plastic wrap to far in.

I don’t have my fork to hand right now.

Just sounds like spring rub. The shrink wrap just gets inserted to the depth to ensure the top of the spring rod sits inside it, its not holding anything in place though, it’d be quickly destroyed otherwise.

That baseplate is what the positive spring sits on as it’s base isn’t it (page 8 of the instructions shows that it sits on top of the spring rod. although the lower photo isn’t obvious that the washer is sitting on the rod, but you never see it again)? It’s not just floating around when the fork compresses

Does this mean you can add more oil? And will the conversion make a big difference to a standard fork?

It will make a difference to a standard fork for sure, probably more so than a damper modification.

You add 10ml of oil to the spring side with this conversion, I think it acts as both a lubricant and a hydraulic bottom out – so adding more may increase the bottom out resistance – but I’m not sure.

It’s not just floating around when the fork compresses

Nothing is floating around in mine, there is just a little preload as the spring is compressed as I screw in the aircap

I think it acts as both a lubricant and a hydraulic bottom out

I do wonder about this, the lower must be pretty airtight so may be acting as an air spring and more oil would mean more effect. But I have no idea how much effect the volumes involved have

Nothing is floating around in mine, there is just a little preload as the spring is compressed as I screw in the aircap

There would only be something not secured down if you put the washer on the air shaft so it sits on the negative spring (if it even fits), rather than on top of the shaft so it’s acting as the seat for the spring

If I remember correctly I fixed a cup containing the top out/negative spring in the bottom of the stanchion then stuck the rod that fixes to the bottom of the fork with a washer for the spring to seat on down the stanchion. This was followed by the spring then the aircap with another insert for the top of the spring. No noises so far but not properly ridden yet…You are making me doubt whether I put everything in the right order. It made sense at the time

Nah that’s exactly what I’ve done too. I’ll open it up and have a play with the spring to see what happens. The noise isn’t loud, would just rather it wasn’t there

I have mine setup with the washer on the tip of the spring rod, to seat the spring. Not sure you guys have done anything wrong.

Anyway, my Pike was my first ever coil fork. I’ve spent plenty of time on coil 888’s, coil Boxxers, Coil old model Pikes, coil Lyriks, coil Totems and coil 36’s. All made some kind of small noise.

Not sure how people notice these things whilst they’re riding, I’m used to my quite heavy compression tunes making really loud squelching noises though. I can’t say I’ve noticed any noise.

Thinking about it, I can’t get my head around why the top out cone that retains the spring is a two piece thing as opposed to attached to the spring collar. I guess the top out spring wouldn’t be effective then?

Doesn’t look to be any different from previous Rock Shox designs really….

How long after ordering did delivery take for you guys?

5 days or so

I ordered evening of Monday 23 Jan and it was in my hands on Wednesday 1 Feb

Just to let you know the update from Tftuned from my additional questions:

“I have no idea of the cost, but I won’t be surprised if there’s not much change from £200.

Yes, either home install or workshop install will be options.

We have plenty of damper upgrades, but the coil conversion will be available individually.

There is a feature with the coil conversion that makes it compatible with the charger damper.

The damper has been manufactured with an air spring in mind.. With a bladder in a cartridge, the damper offers very little ramp up in resistance, and there’s no way to alter damper characteristics with oil volume.

The coil conversion kit will include a feature where the ramp up can be adjusted without altering the initial spring rate. It can be a challenge to find the correct spring rate with a straight forward coil in a new Pike or Lyrik, because the last quarter of travel is relinquished a little too easily, so you increase the spring rate and compromise the rest of the stroke.

The new conversion kit won’t suffer with those characteristics.”

That just makes me happier that I haven’t waited!

^ that is why I previously mentioned the use of tokens. I’m not that heavy nor an especially fast or ‘aggressive’ rider so I’ve never wanted to add tokens to a 160mm pike and I am therefore not expecting to be bottoming my coil. I will be interested to see what TF come out with though

Rubber_Buccaneer – thanks for the reply (last page!). I have played with my Pikes no end to get the best setup. I’m currently on two tokens in order that I can run a slightly lower pressure for better small bump compliance but then having a quicker ramp up. I may toy again with going back to a more linear set up soon as the fork will dive through its travel quite quickly. It’s hard to balance fork dive with small bump compression (lsc is on minimum damping before you ask) and I like the idea of a nice linear spring rate tuned to my weight. I’m really just jealous of the complete lack of sticktion that my mate had on a set of coils, and the low maintenance is a massive boon – with 3 kids riding time is at a premium let alone pulling my forks apart every 30hrs. I’ve done it, and I know it’s not the biggest job in the world, but I just can’t be bothered with it. I’m very much a wash my bike when I get round to it guy… Oh, and I’m on the lighter side (6’3″ tall and 90kg) and I’ve just got that curious coil itch that is eating away at me!

I could really rant about some of this stuff too. I am not good at suspension set up, I really struggle, so when I read stuff like

With a bladder in a cartridge, the damper offers very little ramp up in resistance, and there’s no way to alter damper characteristics with oil volume.

it annoys me a little that it’s sort of true but not really. They are suggesting you want your damper to incorporate an air gap that acts as an air spring to give bottom out resistance. I don’t think adding oil volume is ever going to change the damper characteristics is it?

You’d need a hydraulic bottom out control (ala Manitou) really. Old open bath forks could use changing oil height to good effect, but that was a lot more oil with a much smaller air gap plus specific oil seals (as well as standard dirt wipers) to handle the increase in pressure. When those blew a seal you really knew about it!

Actually, I believe you can alter ramp up on the Pike on the damper side. Its just a bit of a bodge job by either overfilling it so the bladder expands, or reducing the volume of the area the bladder can expand into – just like a bottom out adjuster on a rear shock.

You could also reshim the damper to give a progressive damper tune.

Im not interested in a progressive stroke until the last inch of travel anyway.

Its a challenge to find the right spring rate for a pike or lyrik if you are choosing from 5 rates, it really isnt with 10.

Specifically, you coukd place some closed cell foam around the bladder essentially pressurising the cartridge. The more pressure, the more bottom out resistance – no? This would also reduce the forks chance of cavitating.

Would think so. Manitou (2 mentions in the day? They’re doing well this week) already uses a foam setup instead of a rubber bladder

I thought (and I may be exposing my ignorance if it wasn’t apparent already 🙂 ) that having a sealed bladder pretty much eliminated cavitation?

Nope. Something to do with vapour pressue of the oil….its why all rear shocks are gas pressurised and most high end motorbike forks with bladders or IFPs are pressurised as well. Fox and Rock Shox inexplicably dont do this with their MTB forks.

Its likely fine on RS/Fox forks until you start playing around with heavy mid valve tunes.

I can see that. Reminds me of the ‘degassing’ in Avid’s brake bleeding instructions and seeing bubbles appear from nowhere in the brake fluid

Rubber_Buccaneer – Since you said you struggled with setup this was the set up guide I found most useful. It made a massive improvement for me but I’m still looking for a little more! There’s some nice graphs and explanations in it…

http://nsmb.com/rock-shox-tuning-camp/

I think the other thing is that my last fork was a Bos Deville and it just felt nicer. I can’t put my finger on why, but I’m looking to replicate that. It was certainly better on the small bump stuff – whether that is the open bath system I couldn’t say but it would be part of it…

Thanks

Well, a coil will cure that.

Now time to try and work out where to souce foa. And what density, and ask around if the shimstacks will need retuning if I pressurize the damper.

Theres some guides on the restackor shim calculator website which indicates that pressurising the fork is quite a balancing act.

http://www.shimrestackor.com/Code/Sample_Applications/Midvalve_Bladder/bladder-perf.htm

Not that I think my setup needs any more bottom out tesistance really, the FAST cart resists hard hits exceptionally well. Kind of feels like it has a lot of anti dive/resistance to low/mid events, but the damping blows off on mid-high events and hardens on big impacts…eg drops to flat.

I just like **** about with suspension.

Possibly a daft question but are they 26″ or 27.5 specific? Or swappable?