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New bling coming for my ride!!!

I was having chainline issues on my F-40/P38.
The problem came from the root issue of a too long of a chain. But I needed a longish chain in order to give me the low end I needed (I hit 22% grade for about 30 yards after grinding up 7-8% climb to the top of my hill) and the high end that I want. (ie Going back down!) On the P-38 I cant get it up to ~45mph before I cant overcome wind resistance.
Georgia is very hilly! So when I need a lower gear I really do need it, when I want a higher gear.. I want it. But derailuers only span a range of so far, and trying to accommodate both extreme ends of the spectrum is a challenge.
This problem would manifest itself by sometimes bouncing the chain around to the point that the driveside chain would bounce under the front idler.
The other issue was hard interference between the rear fairing frame, and the rear derailleur cage. When shifting from the smaller cogs to the larger while in teh middle front ring I would need o shift into the large chainring to put more tension in the chain to pull up the Rear derailleur sfift down the cassette, then back to the middle ring. This is bad because while downshifting I am forced to go into my big ring.
The opposite applied while upshifting. In addition there a was alot of overlap in my gears.

So... A set of Schlumpf High Speed Drive cranks popped up on Bentrider! I ordered them and will be sending my boom in Tomorrow (Monday Oct 1) to have them installed!
This means 1 chainring up front. Its a 27T. This will give me an even lower low gear than I have now. On the high side it equivalent to a 67.5T chainring. This will allow me to run a shorter caged rear derailleur in back, thus fixing the hard interference issue.
I'm planning to use a 11-27 cassette, currently I have an 11-32 I have a gear that is the same as my current gearing, and I will be able to on the low side gears 1-9, shift to high side gears 1-9 and never have any gear overlap, with nice even gain ratio between every gear. I will give up 6 gear inches on the side. Or I could use the same 11-32 but with that I'll have 2 overlapping gears.
The price is that there will be 3-5% parasitic drag from the planetary gear system. I will see how that plays out.

I'll get some pics and post them when I piece it back together.

1) There is a rider who sometimes posts notes both here and on BROL who goes by the name ncaudio. I think his real name is Roger V., and he has experience with a thing called a Mountain Tamer quad chainring. Basically, this is a thingamabob that lets you use four chainrings with an ordinary crankset and front derailleur.

I have never tried doing this, but if I lived in an area with lots of steep hills, I probably would give it a shot. You might want to email ncaudio / Roger and pick his brain about this.

2) To get a higher high gear, the Shimano Capreo rear hub and cassette let you use 9 and 10 tooth rear cogs.

3) I think the maximum chainring size for a Lightning tops out close to 60t with a normal front derailleur.

4) I have never used the Schlumpf drive myself. Please write back to us and give us your impressions of the thing after you have used it for awhile, and good luck with it.

Safe riding,
Joel

My HSD came in yesterday and I mounted it to a new boom that I had ordered and took it for a test ride.

The longer boom + cranks weigh in at 1820 grams.
My previous Ultegra triple + shifter weigh 1680grams.
I also went from a shimano LX Long cage rear derailleur to a Med cage rear derailleur. So maybe a few grams for that, and few more for cables. Either way I figure that the Schlumpf system is just under ~140 grams heavier that my Triple system. The new boom is about 1.5 inches longer as well, so that has to add a few grams.

The first thing you notice is how small the entire package is. I was used to looking down and seeing 3 rings with a 56T big ring. Now its just a little bitty 27T ring. Thats it. My bike looks naked.

Shifting is very easy. I use Look Keo pedals and its very easy to tap the shift button.

Parasitic drag is not noticeable. In the 27T setting with no overdrive there is none. In the High Speed setting there is 3-5% parasitic drag but I cant really feel it. I have a Nuvinci hub on another bike and I can say that it feels like a sponge at times with parasitic drag. There is none of this with the HSD.

Gear range
Wow. Using the same cassette that was already on the bike 11-32 I have a HUGE gear range. The best part is that there is almost no overlap of gears. Only 2 gears overlap.
My high gear is an gargantuan 165"! Not sure how I will even use that top gear. I could change to a 12 or 13T based cassette instead of the 11T smallest cog.

This makes my shift pattern Low (1-9) then shift to high and run back through 1-9 on the cassette.
So far I'm liking it. I am going to try it out on a 200K next weekend and I'll see how I like it after more miles.

The shorter caged rear derailleur also fixes the problem that I was having where the derailleur cage would physically hit the framework of the rear fairing. This prevented me from getting into the lower side of my cassette.
Another upside is that my chainline is always the same in front. Nothing rubs so its a quieter ride.
I'll try to get pics this weekend.

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