Simplex Prestige RD capacity
 

According to Velobase, this Simplex Prestige rear derailleur:

VeloBase.com - Component: Simplex Prestige (variant version of AR637P/NI)

has a total capacity of 37 teeth. That can't possibly be right, can it? I'd have guessed 30 teeth at the very most. Does anyone have any real-world experience with this?

Admittedly, the Velobase entry is kind of confusing, in that it has pictures of two slightly different derailleurs, with the cage pivots in different places. The caption mentions that one is the old style and one is the new style, but doesn't say which is which, or whether their capacities differ, as would imagine they do.

Maybe that was supposed to read 27 max.

I just picked up a long cage Prestige from ebay. That might go 37

Which of the two versions do you have?

I don't have either. I'd like to have the version with the larger capacity of the two, whatever that might be.

My first road bike was a Jacques Anquetil gas pipe with a Simplex Prestige and a 14-28 5 speed freewheel. Worked fine until I wrapped it up in the spokes.

To add insult to injury I replaced it with a Campagnolo Valentino.

I'd say it was less a case of "insult to injury" than "out of the frying pan and into the fire."

On second thought, it was probably both.

I started laughing :roflmao: as soon as I read the word Valentino.... :roflmao:

Tullio truly hated his son Valentino!

Getting back to [MENTION=52458]jonwvara[/MENTION] Peugeot used 14-28T FWs and 52-36T chainrings on some U0-8s in the 70's (others were 52-40T). Simplex Prestige derailleurs worked fine with those combinations (when new, well adjusted and lubed, including cables and chain).

The Alpine gearing that was the most common set up on lower end bikes during the early 70's bike boom used 5 speed 14-28T FWs with 52-36T, 52-40T or 52-42T chain rings.

We frequently set those bikes up with 14-32T freewheels. That was 34T which is the published limit for standard Simplex Prestige RDs.


There are 2 different specifications for derailleur capacities:

One is the largest size freewheel sprocket that a derailleur will work with. The other relates to how much chain the derailleur can wrap up.

Formula for Second spec: Number of teeth difference between the smallest and largest Freewheel sprocket plus the difference between the small and large chainrings teeth.

For example: Freewheel, 28 -14 = 14 Teeth. Chain rings, 52 -42 = 10 Teeth. 14T +10T = 24T


The Simplex AR 637 NI/P is a direct mount derailleur for attaching directly to a dropout with an integral hanger. The /P indicated that the derailleur came with a detachable claw hanger. These were not very common.

Millions of standard Simplex AR 637 P derailleurs were produced from the mid 60's until the mid 70's. They had an integral claw hanger. See parts breakdown below.

http://bikeforums.net/attachment.php...hmentid=491878


Velobase.com is a great resource, much like Wikipedia, but information can be posted by anyone so those sites shouldn't be taken as gospel, just reference points.

The derailleur described as a Simplex AR 637 NI/P is WRONG.... It's a standard AR 637 P... (I'll contact the webmaster and get it corrected)


Clear as mud eh?


Simplex produced the Maxi Prestige ref AR 642 with a long pulley cage and a long claw hanger attachment. They were uncommon. I've only seen a few of them and that was back in the early 70's.

http://bikeforums.net/attachment.php...hmentid=491877

The 1972 Simplex catalog lists the capacity as 13 e 30 dents meaning 30T large sprocket. Sutherland's lists 36T maximum freewheel size and 39T chain wrap capacity.


Back in the 60's the French used granny gears on the chainrings on a lot of touring bikes. A double might have a 48T to 50T large chainring with a 26T small ring. Triples had 1/2 step gearing with a granny gear, for example 50-47-26.


Both the Simplex Maxi Prestige and the Huret Super Alvit long arm derailleurs worked best with a large difference in the number of chainring teeth and a small differenc on the freewheel - like a 13-24T or 13-26T FW.

They could handle large freewheel sprockets but never shifted very well. By the early 70's Suntour ate their lunch with inexpensive long arm derailleurs that actually WORKED with zero futzing!


So, a standard Simplex Prestige will work OK especially if you are trying to keep your bike original.


BITD in the day Simplex derailleurs were so cheap that if we couldn't get one working right within 5 minutes on a repair job, we just chucked it and put a new one on the bike for under $10 including a new cable and labor!


I never thought that I'd EVER spend good money on a Delrin bodied Simplex derailleur but I've bought 2 or 3 better quality Criteriums for my my classic French bikes! :eek:

verktyg :50:

Chas.

I have a long cage version on the SX410. I'm using a 13-30 five speed freewheel and a 46, 42 & 30t chainring set. Mine is a direct mount, without the claw, see: VeloBase.com - Component: Simplex SX410 GT (long cage)

Any opinions on this drivetrain?

Thanks, Chas.

The beauty of old Simplex stuff is that not only did they make lots of different variants and sub-variants of the same item, but they also didn't seem to worry overmuch about stamping identifying numbers on the parts themselves, unless I haven't been looking hard enough. Doubtless it was easier when the stuff was new and you had the original box.

My guess of a 30-tooth capacity for the basic derailleur found on the zillions of UO-8s was based on the memory that most of the UO-8s I used to see were 52-36 in front and 14-28 in back. I'll see how that does with a 52-42-32 triple with 14-28 in back. It may work fine (for Simplex, that is) as long as you don't use the 14- or 17-tooth cogs in the granny ring.

As you suggest, any idiot can get Suntour gear to work perfectly, but Simplex? If you can coax halfway decent performance out of Simplex equipment, you're a real mechanic.

We should probably have an entire thread on tips and techniques for pushing the freewheel size and chain wrap limits of various derailleurs beyond their published specifications. Exact choice of cog and chainring sizes, length of chain, setting of mounting tilt screw or pivot spring tension, length of derailleur hanging tab or orientation and length of hanging claw, size of jockey pulley, and position of rear axle all play roles here.

I have found the Prestige works best with the shortest chain possible. I tend to use 14-22 or 14-24 freewheel with 40-52 or 45-52 chainrings. I get the best shifting from a chain that is tight, no extra links. Suntour and other slant parallelogram derailleurs can wrap up a lot of chain and chain length isn't as critical.

As long as the granny gear is not used with the 14 or 17 cog I think you will be fine. The long cage Prestige would be the way to go with your setup though. It can wrap up a lot of chain and it has a lighter touch when shifting.

Undocumented variants! :bang:

The closest I can think of off the top of my head were "some" of the late 60's early 70's Criterium RDs had a date code stamped into the inner pulley cage.

http://bikeforums.net/attachment.php...hmentid=491903 http://bikeforums.net/attachment.php...hmentid=491904


All of the published information I've found for the Simplex Criterium derailleurs list the capacity the same as the Prestige. BITD we found a number of Gitane TdFs had Criterium RDs with shorter cages and would only handle up to a 26T large FW cog!


The only thing close to a universal marking on Simplex derailleurs is "SGDG" Sans garantie du gouvernement which means without guarantee of the government - in other words not patented (as opposed to Brevete meaning patented).

Simplex boxes were/are no guarantee that what's in them matches the label. Especially on a 30 to 45 year old box. At our shop, people would throw things in any old box, we knew what they were so it didn't matter! ;)


What I've found is that the 2 or sometimes 3 smallest sprockets weren't usable an many older triple setups because of chain drag on middle chainring, especially with 1/2 step and a granny gear. Many of the newer triples had more evenly spaced chainrings like 48-38-28T.


Historical perspective... In the 1950's and 60's plastic was considered the miracle material! Cheap, moldable, in some cases durable... By the mid to late 60's plastic became equated with CHEAP in the US: Jefferson Airplane's "Plastic, Fantastic Lover"...

The development of Delrin plastic derailleurs was a collaboration between Simplex and Peugeot at the beginning of the 60's. It took Simplex until the mid 60's to work the bugs out and make their derailleurs rigid enough to shift reasonably well.

Because Simplex derailleurs has a spring in the upper pivot, they "could" work better than Campy RDs! Frank Berto the author of the "Dancing Chain" was always on Campagnolo's sh*t list because he empirically demonstrated that other brands of RDs shifted better!


Mean while, back in the USSR er, USA, customers who spent just $250 to $350 USD on a "fancy" bike were not pleased with plastic derailleurs, especially when they didn't work right!

In steps Suntour with their V all metal derailleurs for $6.00 and VGT long arm for $7.00, keep the customer happy!


While writing this, I just remembered something about setting up Simplex RDs. The rear triangles and dropouts were rarely well aligned on lower priced bikes. Any time a Simplex RD wasn't shifting properly and all of the usual suspects checked out, we'd make sure that the dropouts and claw hangers were properly aligned with the axis of the rear wheels! makes a world of difference.


BTW. something that I noticed BITD was that owners of many French bikes who rode a lot changed at least their rear derailleurs from Simplex to some other make. Most Peugeot owners, especially those with PX-10s stuck with Simplex...
verktyg :50:

Chas.

I found it interesting to hear that a standard-cage Prestige mech could handle anything like a 34 t freewheel size.

Wouldn't the pulley contact the teeth of even a 30 or 32t cog?

I have noticed that Prestige derailers seem to have left the factory in different states of adjustment to the cage spring tension, depending on what freewheel the bike originally came with.
I've had to adjust the chain gap of the standard Prestige for different size freewheels, but as John E posted, there are so many other variables like chain length, etc. that one can't make easy assumptions about what the basic prestige might need in different applications.

The Simplex mech's all seem to have the cage pivot bolt lock-nutted rigidly to the cage plate, and by loosening this external locknut one can effectively adjust the "A"-tension and so effect the chain gap. All that is needed is the open-end wrench for the nut and a 5mm Allen key for the bolt, and the cage held with one's hand while the bolt is rotated a bit to either loosen or tighten the spring tension before the locknut is tightened.
Note that the "A" or cage pivot spring tension affects the chain gap in the opposite way as does the "B" tension screw on a more-modern derailer, i.e. that tightening the cage pivot tension (by rotating the cage pivot bolt counter-clockwise relative to the cage) will reduce chain gap instead of increasing it, so would suit a smaller freewheel.
Somehow I doubt that many people mess with the cage pivot tension, but it can really help with getting the mech to shift well.

David,

I don't think that we ever tried a 34T freewheel but 30T and 32T worked most of the time without having to mess with any derailleur tension adjustments.

Most of the bikes equipped with Prestige derailleurs had long chainstays. Adding a link or two to the chain was usually all it took to jump from a 28T freewheel to 30T or 32T.


The plastic Simplex Prestige shift levers were a p*ss poor design. They never stayed adjusted and/or broke easily.

Most customers who had "10 speed racing bikes" had little or no experience with derailleurs! They brought their bike in for service when their chains skipped too much.

In New Mexico rain was rarely a problem - sand and grit was! The chains were usually so dry that they squeaked plus they'd been riding in one gear combination for so long that the FW cog was worn out and skipped.

The combo was usually either the small-small sprockets because the shift levers wouldn't stay adjusted or for some reason, the 52-24T combo on a 14-28T FW.

We imported 14-28T Normandy freewheels in bulk pack wooden crates of 100 and bought 50 or 100 meter lengths of Sedis chain on wooden spools. Never messed around, just installed new freewheels and chains. Parts sold for around $10 and with labor, the customer was out the door for $15!

We always did a safety check and also tried to educate our customers on how to get the most benefit out of their derailleur bikes.

Most of those folks would have been better served with a bike with a 3 speed SA hub and upright bars but they were carried away with the 10 speed fad!

Because it was so hilly in the area, customers frequently asked for lower gearing. That's why we figured out how to set up Simplex Prestige RDs with 30T and 32T FWs.


The 34T figure was the published chain wrap capacity not the largest freewheel capacity.


verktyg :50:

Chas.

Good point about the chain length, I'll add that it takes only two extra links in the chain (that's one inner link and one outer link) to accommodate a 4-tooth larger front or rear sprocket, since the chain wraps only half-way around.

I've come to reasonably friendly terms with the plastic levers, although they have a sharp edge along the forward side that acts as a limit to the lever's forward travel. After my finger gets poked enough times I eventually round off the plastic's sharp edges with sandpaper and that problem becomes far less bothersome.

If the levers ain't broke, they will likely never break with me using them. This because I never have to use more than fingertip pressure to shift over the entire range. Bikes with poor cabling (and/or perhaps a too-tight lo-limit adjustment) will have the rider using heavy palm pressure to shift, at which point the lever suddenly seems flexy and is prone to breakage. No kidding, I did say fingertip pressure (and no more), since these derailers have a quite-flexible limit peg that poorly controls the lo-limit of travel if heavy shifting forces are applied at the lever.

The friction characteristics of Simplex shift levers is poor immediately after a required (as after sitting idle for 30+ years, lol) lubing, but the plastic and metal friction/rubbing surfaces soon manage to contaminate the fresh lube sufficiently so that the friction character becomes appropriate to achieving premium shifting performance. I've put in the hundreds of miles on many a Simplex-equipped bike that I had just refurbed, and they all came around to having accurate friction behavior within the first hundred miles or so. I also use a little Loctite on the screw as I believe that I have sometimes managed to knock the lightly-tensioned wing nut loose with my hand while shifting. Such loosening always seemed to occur suddenly, which tells me it's not the lever movement that causes the tension to go slack suddenly, how could it?

Lastly about Simplex rear mech's, I often struggle to fit a wider, 6-speed, standard-spaced freewheel onto older 120mm-122mm bikes, and find that while I can achieve needed running clearance for a modern chain with (at most) a 2mm washer added to the driveside axle spacing of a Normandy/Atom rear hub, these Prestige mech's struggle to pull the chain far enough toward the driveside in order to reach the smallest cog. I end up beveling every third tooth of the second-smallest cog (using a Dremel) in order to assist the chain moving quickly off that second-smallest cog.

All in all, I'd say that the Prestige mech's and shift levers can give pro-level shifting performance when used with appropriately-mated freewheel and chain.

The UO-8s that Bicycle Exchange sole in 1967 came 52-36 x 14-26. My friends bought these. I had my FW swapped to a 28 and destroyed several derailleurs. Granted my bike was not very well serviced but it was also obvious that I was pushing the physical limits of the plastic bodied derailleur with my setup. I would strongly advise going to narrower gearing if you choose to go Simplex unless there is concrete evidence that the later Simplexes were of a different geometry or construction.

Ben

That sounds like the case of a somewhat too-tight chain, i.e. some combination of too-short chain and axle (derailer claw) position left in a rear-most position in the dropout slot.

My Steyr Clubman came stock with 52-36 and 14-28t, which worked smoothly and reliably until I fitted a 13-24t five-speed UG freewheel and slightly tightened the Simplex Prestige cage pivot spring to tighten up the chain gap between the top pulley and the 4t-smaller freewheel.
I found this gearing (and shifting performance) to be suitable for the more-sporting group rides here in the foothills. I challenged myself to keep up on the usual rides using only five cogs when I found that the Phil-hubbed wheelset I wanted to use would handle five cogs and no more, and then I surprised myself by keeping up on those rides!
That said, I find that I prefer using a 52-42 chainset with a 13-28t six-speed UG freewheel, which yields that exact same range of gearing while needing relatively little modification to a typical, English-threaded Normandy hub's rear axle spacing.
For reference, 36/24 = 39/26 = 42/28 = 45/30

I have this derailleur and it did not play nicely with a 28T freewheel. 52-40 in front.