Frequently Asked Questions  -  Mountain Tamer

Mountain Tamer Triple Istruzioni Dettagliate di Installazione

SELECTION
Q.  Which Mountain Tamer Adapter should I use?
A.  Use the Mountain Tamer Triple when you want:

  • a triple chaining smaller than 24 teeth
  • four chainrings and your triple chainring will be 26 teeth or greater
  • to experiment with a triple or quad setup
A.  Use a Mountain Tamer Quad Plus when you want:
  • four chainrings and your triple chainring will be less than 26 teeth
  • four chainrings and ease of chaining the size of the triple chainring
  • four chainrings with the quad being 16 teeth (16 tooth chainrings are sold out)
  • five chainrings (requires a modified front derailleur and long chainline)
A.  Use a Mountain Tamer Quad when you want:
  • the lightest possible quad setup
  • four chainrings with the quad being 16 teeth
INSTALLATION
Q.  How can I tell if my spindle is long enough for 4 chainrings?

Q.  How can I tell what length spindle I have now?
A.  Go to Sheldon Brown's incredible site and check out his Bottom Bracket Size Database.

Q.  How can I move the crankarm over to accommodate 4 chainrings?

Q.  My crank doesn't have spacers.  What can I do?
A.  You can cut the bosses off.  Here's how.

Q.  How do the chainrings attach to the Mountain Tamer Adapter.
A.  The chainrings slide onto splines like they do on a cassette. A wave spring maintains tightness and the retainer locks it all together.
                 

Q.  I'm not comfortable cutting the bosses.  Can you cut them for me?
A.  Yes.  The fee for this service is $30 plus shipping costs.  Carbon fiber cranks add $40.

Q.  I have carbon fiber cranks.  How do I cut the bosses on them?
A.  Do not modifiy any carbon fiber component unless you have experience working with carbon fiber. Inhalation of carbon fiber dust can have serious health risks.

Q.  I want to run a very wide range on my chainrings.  How do you get the front derailleur to handle that?
A.  Here's how to do it.

Q.  How do you install the retainer on the adapter (under reconstruction - contact me if you need this)
A.  Here's a video showing the procedure.  (1.5 Mb)

Q.  How do you remove the retainer from the adapter
A.  Here's a video showing the procedure.  (497 Kb)

COMPATIBILITY
Cranks-Chainrings
Q.  My crank has 4 arms instead of  5.  Can I adapt to a lower gear?
A.  No, the Mountain Tamer adapters mate only to the 5 arm-74mm bolt circle.

Q.  I have a Shimano XTR-M950 Crankset with a 4 arm spider.  Is it possible to change it to a 5 arm spider?
A.  Yes.  There were several 5 arm spiders made with 74mm bolt circle available for various cranks with removable spiders. Check for availablity.

Q.  My triple chainring is 22 teeth.  Can I get a lower gear?
A.  If your crankarm spider has 4 arms, that is as low as you can go.  If it has 5 arms and a 58mm bolt circle you can go down to 20 teeth. 
If  your cassette does not already have a large cog of 34 teeth, you can change the cassette. Some are now made with 36 teeth.

Q.  Will the Mountain Tamer adapters work with my Rotor Cranks?
A.  No, the Rotor Cranks have a 4 bolt pattern

Q.  Can I use cogs from a Shimano cassette on you adapters?
A.  No.  The splined cogs are Suntour 'A' freewheel cogs.  The threaded cogs are Maillard 700 freewheel cogs.  Neither is in current production. 
If you find anyone who has the 'A' cogs, let me know.

Q.  I see you have run out of some of the chainring sizes.  Will they be available in the future?
A.  I may produce the 17 tooth splined rings at some time in the future.

Q.  Which position holds the 'A' cog on the Suntour Freewheels?
A.  The two largest positions.

Q.  Which freewheels used 'A' cogs?
A.  Suntour Winner, New Winner, Winner Pro, Perfect.

Q.  How do I get the cogs off of the freewheel.
A.  Using a pair of chain whips or a chain whip and a sprocket vise untread the smaller cogs (CCW). The larger cogs are splined and just slide off.

Q.  I would like to run a 16 tooth quad with a 52 or larger outer chainring.  Will the derailleurs handle that?
A.  You will have to modify the derailleurs.  Click to see how.

Q.  Can I remove my outer chainring a use the quad chainring as a triple?
A.   Yes. You will still need to move the crankset over ~1/4"  (6.3mm)

Q.   What is the smallest chainring I can put in the middle position on a 74/110mm BCD crankset?
A.    34 teeth

Q.   What is the smallest chainring I can put in the middle position on a 74/130mm BCD crankset?
A.    38 teeth

Q.   Can you supply cranksets with a 74mm BCD?
A.    My suppliers no longer carry any cranks with 74/110mm BCD.
        Check with Andel Enterprise Co. Ltd. http://www.andel.com.tw/ for 74mm BCD cranks. They also have an eBay store.
        Search on eBay.  'crank 74' usually gets some hits.
 
Q.    Can  I put  a Mountain Tamer Adapter on my kid's bike, which only has one front sprocket?
A.     That depends. If the crank is not a single piece crank and the crank has 5 arms or a sprocket that can be drilled to allow the adapter to bolt to it.
Drill the 5 holes through the crank or sprocket to match the adapter. You may have to use spacers between the adapter and the crank or sprocket.
If either is too thin to hold threads, use nuts on the chainring bolts.
Q.    Why can't I use the 16T chainring with the Mountain Tamer Triple?
A.     The 16T  chainring  has an intergal spacer,  It will not fit in the space of the other chainrings. 

Q.    What is the inside diameter of  the adapters?
A.     The inside diameter of the adapters is 1.830"

Q.    What is the outside diameter of  the small chainrings?
A.     The outside diameter of the chainrings:
16 - 2.710"
17 - 2.860"
18 - 3.015"
19 - 3.150"
20 - 3.350"
21 - 3.490"
22 - 3.645"
24 - 3.980"

Bottom Brackets - Spindles
Q.  I have a Fisher mtb with an oversized bottom bracket.  Will the Mountain Tamer adapters fit over it?
A.  Yes.  The inside diameter of the adapters is 46.5mm (1.830")

Q.  My bottom bracket has a locknut on the right side.  What is the inside diameter of the adapters?
A.  The inside diameter of the adapters is 46.5mm (1.830")  Be sure to allow some clearance for mud, etc.

Q.  My bottom bracket has outboard bearings on the right side.  What is the inside diameter of the adapters?
A.  The inside diameter of the adapters is 46.5mm (1.830")  Be sure to allow some clearance for mud, etc.

Q.  Can I replace my cartridge type bottom bracket with the old type spindle with ball cups?
A.  Yes.

Q.   What  are standard bottom bracket shell widths.?
A.   Standard bottom bracket shell widths are 68, 70, and 73mm. Most mountain bikes are 68mm, though some are 73mm. Road bikes are usually 70mm.

Q.   What does the spindle or bottom bracket length refer to?
A.    The length is the distance of the spindle measured from end to end in mm. Some spindles have studs instead of bolts.
        They are measured from the end of the interface surface, not the end of the studs. In most cases, one side is longer than the other.

Q.    What does 1.37" x 24 tpi means on the bottom bracket?
A.     1.37" diameter  -  24 threads per inch

Q.    I need a longer spindle.  My bottom bracket shell is 68mm. Can I use a 73mm bottom bracket and spacers.
A.    Yes. Just make sure you have enough threads engaged.

Q.    I can't get the bottom bracket cup on the chainring side to come loose.  What do I do?
A.    The right hand cup has left hand threads. Turn clockwise to loosen the right-hand cup.

Q.    How can I tell if I have a square taper spindle?
A.    Remove the dust cap and bolt from one of the crankarms. You will be able to see the end of the spindle. Retorque the bolt when finished.

Q.    Are bottom bracket spindles or BB cartridges symetrical?
A.    No. They are longer on the right side (crank side) than the left.

Q.    What are the bottom bracket interface designations?
A.
JIS:    square 2 deg. taper
ISIS:  10 spline taper - 16mm deep
HT2:  Shimano Hollowtech-II integrated spindle with outboard bearings
OL5:  8 spline 5mm deep - Shimano Octalink (105,DuraAce, Ultegra, XTR)
OL9:  8 spline 9mm deep - Shimano Octalink (Deore, LX, XT)
Note:  older Shimano Deore, LX, and XT cranks used JIS
SP8:   8 spline on CrMo cranks
SP8:   10 spline on CrMo cranks
SP8:   36 spline on CrMo cranks
SP8:   48 spline on CrMo cranks
PS:     Truvativ PowerSpline
Howitzer:  Truvative
MegaExo:  Full Speed Ahead

Shifters
Q.  Will the Mountain Tamer Triple work with my indexed shifters?
A.  Yes, the chainring will be in the same position.

Q.  Can I run four chainrings with my Rapid-Fire shifters?
A.   No,  unless you add a device such as the 'GIZMO' once sold by Sidetrak which gives you a high range/low range capability.

Q.  Will Grip Shifters work with four chain rings?
A.  Yes, as long as they are not indexed.

Derailleurs
Q.  Will my front derailleurs handle four chainrings?
A.  Yes, though it is important that the crankset be position correctly for it.

Q.  I want to go to the quad setup with a 16 tooth chainring.  Will my rear derailleur be able to handle the chain wrap?
A.  Yes,  keeping in mind you should not use the quad chainring with  the smallest cogs on your cassette.

Q.   I would like to run five chainrings. Will I have to modify the derailleur?
A.   It's highly probably. I'm willing to help you with the details.

Gear Charts
(Under construction - contact me if you need this)

Other
Q.  Will my 9 speed or 10 speed chain work?
A.  Yes

Q.  Can I use the Mountain Tamer adapters in conjunction with an internal hub?
A.  Yes, with a caution.  Some hub manufacturers specify a minimum recommend chainring.  If you're not real strong you may get by going smaller.  If you want to do this, contact me for more advice.  I have quite a bit of experience in this area.

Q.  Can I use the Mountain Tamer Plus with five chainrings with 10 cogs on a 14 speed Rohloff hub?
A.  Theoretically,  with some serious modifications like a custom frame and a modified cassette, I don't see why not.  Of course, you would void the warranty on the hub.  ...hmm 700  speeds.  Are you trying to get into Ripley's?

Q.  Ok. So what's the most gears you've seen?
A.  I built a bike with 120 speeds back around 1964.  It used 4 chainrings with 6 cogs on a Strumey Archer 5-speed hub.  At that time, 6 cog freewheels where rare, as were triple chainrings.  The bike had a gear about every 2" and a range from 10" to 156".  I rode it 5000 miles before the frame failed. 

USAGE
Q.  How much difference does one tooth make on the chainring?
A.  Roughly, each tooth difference below 20 teeth equals one gear.  From 20 to 28 teeth, 2 teeth equals a gear.

Q.  How many of the cogs on the cassette can I expect to use, practically, with the quad chainring?
A.  This will depend upon several factors:  chainring size, cassette size, chainstay length,  chainline, and chainwrap of the rear derailleur.  Typically the gear ratios will start to overlap around the 4th cog.  You can expect to use 3 to 5 of the largest cogs on the cassette with most setups, more with a long chainline if you can wrap the chain.

Q.  Will I be able to balance with such a low gear?
A.  Of course.  You will actually be going about the same speed you where before.  The difference is that you will be able to spin faster, which is much more efficient.

Q.  When I climb really steep stuff, my front wheel comes off the ground.  What should I do?
A.   Drop your shoulders.

Q.  Where should I be on the saddle on really step climbs?
A.   Position yourself over the saddle such that your weight is driving through the ground contact point of the rear wheel or as close to it as possible.

Q.  How steep can I climb with such low gears?
A.  Anything you have the guts to stay on the bike. I have climbed  stuff on slick rock where I was standing up with my chest against the handlebars.  The thought of breaking a chain was very distracting.
Q.  How can I tell if my spindle is long enough for 4 chainrings?
  • Shift the front derailleur  to the triple position.
  • Measure the distance between the inner arm of the derailleur and the seat tube (or equivalent)
  • If you have 8mm (.310") or more,  your spindle is long enough.
  • If not, subtract the measurement from 8mm. 
  • This is the minimum amount the crankarm needs to be moved to the right.
  • You also need 9mm space between the chainstay and the triple at the diameter of the quad.
  • Also check the distance between the chain and the tire when shifted into the lowest gear.
  • You can go to Sheldon Brown's incredible website and check out his Bottom Bracket Size Database to find what length spindle you have now.


Q.  How can I move the crankarm over to accommodate 4 chainrings?

A.  Some spindles are adjustable.  Simply adjust as needed.

If the distance needed is less than 3-4mm
  • Measure the distance between the left chainstay and the crankarm (in the 3:00 position facing it)
  • If there is enough room, the bottom bracket can be shifted over by using spacers between the right BB cup and the BB shell.
If those methods won't do it, a longer spindle or bottom bracket cartridge is required.
Remember,  typically, but not always, half of the additional length is added to each side.

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10/10/2012