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Discussion Starter · #1 ·
Couple weeks ago I posted up my Nomad 1 with the Hammerschmidt using a custom ISCG adapter. I let a buddy of mine try it on a ride, and he liked it so much that he decided to try one out on his Nomad 1. Only we decided to see if it could be done with less custom work using an off the shelf adapter with small modifications....

The adapter we used was the MRP ISCG 03 adapter:
Material property Watch Plastic Watch accessory Number


As with my install, the adapter takes up 2.5mm of BB width, so had to remove 2.5mm of material from the BB shell on the drive side. Nomads come with 73mm BB shell width, so we brought it down to 70.5mm, so that with the MRP adapter, the total width is 73mm:
Pipe Cable Wire Security Steel


Once you cut the BB shell down, and put on the MRP adapter, you can see that the back side of the adapter wants to hit the rear bearing boss in the frame when trying to rotate the adapter clockwise (looking at it straight on from the drive side):
Carmine Synthetic rubber


This is important because when in overdrive mode, the hammerschmidt wants to rotate the ISCG adapter clockwise, and now that the BB shell has been faced down, the adapter won't rotate due to the bearing boss being in the way. The only issue was trying to figure out if the adapter was clocked correctly.

We installed the hammer's alignment guide and it appeared to be slighly off. It's hard to see where the tape measure is supposed to intersection the arrow on the alignment gauge, so I drew a red arrow on where the tape measure should have overlapped:
Finger Wrist Composite material Steel Synthetic rubber


If we decided to use it as is, I think it would work. In fact I think it would put the shifter housing cable in a better spot (closer to the frame, and less likely to get bashed by rocks). The second issue with the incorrect clocking is that the upper chain guide might not be able to rotate enough forward to prevent chain interference during full suspension compression.

Because he was so intent on having the alignment spot on per Truvativ's spec, we clocked the ISCG adapter where to Truvativ's alignment specs and scribed a cut line on the MRP adapter:
Automotive exhaust Steel Machine Synthetic rubber


Grey Metal Household hardware Circle Iron


Then modified the adapter a little:
White Cable Black Technology Grey


After the mod, the ISCG adapter aligned up perfectly with the alignment gauge and there was a nice flat interface between the modified area and the frame:
Metal Steel Aluminium Silver


Finished install pics:
Vehicle brake Machine Metal Circle Disc brake


Bicycle part Bicycle wheel rim Bicycle drivetrain part Bicycle chain Spoke


Neither of us was sure if there was enough material there on the ISCG adapter to create a proper interference to prevent rotation. But a few parking lot sprints in overdrive mode proved to hold up ok, so we headed out to the trails for a test. So far on one ride, it's holding up great and he LOVES the instant shift!

Moral of the story?.....

I think the un-modified MRP adapter would work even without the little cut we made on the back side if you use the 22T chainring with the 24T upper guide and just clock the upper guide as far forward as you can. This means that anyone who has access to a BB shell facer to cut down 2.5mm off the drive side of their BB shell (or get a shop to do it for them), could basically just buy the MRP adapter and run the hammerschmidt.

But then again, he's only got one trail ride on it - and this setup I believe needs a more testing on it. I'm gonna forward this link to him, so he can update his impressions on the setup himself.

:D
 

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Another great post on hammerschmidt install. I had wondered about ISCG adapters and if they could be used without rotating on their own. Very interested in hearing the results after a month or two on the system :thumbsup:
 

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Trimming/facing th' bb on the drive side has to change the chain line...right? I'm guessing it isn't an issue due to the Hammy eleminating th' ft derailluer ?????

School me & set me straight here...
 

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cosmoworks said:
Same chain line. The amount of width we take off with the facer is added right back on with the ISCG adapter. So the net effect is same BB width, same chainline.
Figgered that out after I headed home yesterday.....duh...silly me...:madman:

Guess I jus' needed someone to state the obvious...lmao
 

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First two rides

Took the new Hammerschmidt on the second run last night and it worked flawlessly. The shifting is fast and butter smooth. I put a short cage derailleur on the back since the first ride (nice advantage of the Hammer) and now I can shift almost as fast with the rear derailleur. The ISCG adaptor hasn't budged and I put the cranks under some serious strain a few times. Cranks have more dirt on them but no worse for wear. I'll give another update after a few more hard rides. :thumbsup:
 

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So someone explain the Hammerschmidtne system to me.

What is it? wherer does it go? Does it work and how. Will it work on my bike (sc bullit) and do I need it. Most of all is it durrable and light. $$$$$$$$$s?
THANKS
 

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geinsteder said:
What is it? wherer does it go? Does it work and how. Will it work on my bike (sc bullit) and do I need it. Most of all is it durrable and light. $$$$$$$$$s?
THANKS
Search :skep:
Every single one of your questions has been answered already.
 

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Another weekend of riding (mostly downhill) and the ISCG adaptor is still solid. I've worked it pretty hard, hit the cranks a couple times on rocks and it hasn't moved at all. Next weekend is DH in Tahoe so it will be another good test.

The hammer is a nice addition to the nomad for all mountain/freeride. I love not having to worry about my chain falling off in the rock gardens. And chain slap is a thing of the past.
 

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Discussion Starter · #10 ·
Found out that the bash guard is made of carbon fiber while riding with timight this weekend. Rock shot up from my front tire and pinged the bash delamanting a part of it.

The weight weenie side of me is partially relieved that I shed 0.5 grams off my 38 pound Nomad. :D
 

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@cosmoworks: may I ask, how did you grind the BB shell? It looks like a non easy task at least if done with "regular" equipment.
TIA for the answer
 

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thanks timight, I knew about this tool, but selling for around 500$ is a rather expensive "toy" for a 1 time use. I was hoping for something more home-made/creative, but I guess is hard ;-)
 

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Well, another creative/homemade approach that I thought about was clapming it to my mill and facing it that way. LOL

I had no desire to screw up on this one and have to figure out "creative" way to FIX my frame. I was lucky as I have a friend that has the tool. After using the tool there is no way I'd attempt this mod without it. If you decide to go for it without the tool just make sure you measure the shell length often and in several places.
 

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Just did three days of downhill at Northstar in Tahoe and the adaptor is in perfect condition. Hasn't budged at all. One insight that was gained from all the riding has to do with how much metal you take off of each side of the frames bottom bracket shell. My friend took more material off of the non-drive side of the cranks and his chain makes more noise when riding intense terrain. I only cleaned up the non-drive side and took the remainder of material from the drive side. While my chain still hits the sides of the hammer guides it doesn't make quite as much noise. I love the Hammer and the cheap ISCG mod works great.
 

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Hammer on the Nomad

Cosmoworks, how does the Hammer impact pedaling if at all? SC told me the Hammer essentially will pedal and feel like you are always in granny gear thus exposing more pedal feedback in the VPP. In your opinion is this true?
 

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Discussion Starter · #17 ·
Namrek said:
Cosmoworks, how does the Hammer impact pedaling if at all? SC told me the Hammer essentially will pedal and feel like you are always in granny gear thus exposing more pedal feedback in the VPP. In your opinion is this true?
IMO, in theory they're right. However that being said do I actually feel more VPP feedback in real life? No.

Obviously VPP feedback is exactly the same on the hammer as a standard crankset when comparing non-overdrive modes to the small chainring. The difference in feel comes into play when the hammer is in overdrive mode. Since the hammer's chainring pulls on a slightly different angle than a true 32-34T middle chainring, it would in theory cause the drivetrain to resist chaingrowth more. Which should translate into more locking up of the suspension while pedaling in the overdrive mode.

I can tell you that in the 3 days I spent at Northstar riding with timight, I was extensively in the overdrive mode and didn't notice any additional feedback effects over the standard 2-ring setup that I took off. I think you simply don't feel it because the effective gear ratio is high and VPP feedback just isn't large enough to notice like it is in the lowest of granny gears.

Hope that helps.
 

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Hammer feedback

Thanks for the feeback. Sounds good. Last question...maybe...do you climb on the bike or are you mostly shuttling or riding lifts?

I really like the idea of the hammer on the Nomad and was thinking of doing this next spring but SC kinda turned me off of the idea. Your thread has re sparked my interest. :thumbsup:

Thanks
 

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Discussion Starter · #19 ·
Namrek said:
Thanks for the feeback. Sounds good. Last question...maybe...do you climb on the bike or are you mostly shuttling or riding lifts?
Thanks
My usual practice is to earn my downhills, so typically I do a lot of climbing... so I guess that makes me "all mountain". But when a free lunch (lift or shuttle opportunity) comes along, I take it! :thumbsup:
 

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That's cool. I'll take a lift when I can get one too. Just trying to figure out if you were climbing on that bike with the Hammer and when climbing you felt more pedal feedback than other times? Thanks for your answers.
 
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