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New Crank Forward - First Impressions



 
 
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  #1  
Old November 23rd 08, 05:23 PM posted to rec.bicycles.tech
slide
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Posts: 55
Default New Crank Forward - First Impressions

Due to major back injuries / surgeries, I sold my conventional diamond
frame bikes and bought a Rans CF bike called the Dynamik. This isn't a
recumbent but rather a 'real' bike but in the form of an Electra Townie.
Supposedly the Rans is as fast and climbs as well as a conventional
bicycle but is more comfortable. Here's a link:

http://www.ransbikes.com/Dynamik07.htm

The bike is enormously comfortable. It took a lot of adjusting with the
seat height and the seat angle to get it to feel right, but it is there.
The sit up position makes riding a true pleasure. I'm riding in street
clothes with hiking boots. Again, the clothes make for a very
comfortable ride. It's also pleasant when reaching a destination to get
off the bike, lock up and then be dressed conventionally rather then
clunking around in Spandex and stiff shoes.

The sit up position is easy to like. I'm riding down courses I've ridden
perhaps hundreds of times before but seeing things I'd missed time and
time again on conventional bikes. I also think the safety element is
much higher because I"m up and looking about and can swivel my head to
see behind me easily. Thus I'm more aware of my surroundings,
traffic-wise, than on a conventional drop bar bike.

The front end is way out there making it lighter than a conventional
bike. Thus it'll wash out easier on gravel or loose dirt. I know from
experience. However, the seating position makes it easy to recover from
a washout.

I'm skeptical that this bike will climb like a conventional bike. The
technique is a bit different. Instead of standing to climb (you CAN
stand) you pull back on the bars to put more power into your legs. So
far this isn't as effective for me as standing but I am able to climb
hills if in a lower gear. Also I"m a bit out of shape so this may be
something which comes in time.

The bike is probably as fast as conventional on a level surface. It
flies downhill. But there is a gotcha in a way. Being upright, I"m more
susceptible to wind. My first ride was into a 20 mph wind outbound. It
was tough going due to the sitting position. However, at turnaround, I
was going downwind and the bike flew. I hardly needed to pedal. It was
like I'm a windjammer craft. So IMO, the bike isn't as good in high
winds although if it were always downwind...

The only real dislike I have for the bike is the grupo - specifically
the SRAM X.5 gears. My conventional bikes had Record 10 and Shimano XT.
This grupo doens't shift well and will even shift itself. The twist grip
shifters seem attached to elastic cables. The entire shifting experience
is unsure and unsatisfactory. If I grow to use this bike a lot, I'm
upgrading to XT's.
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  #2  
Old November 23rd 08, 06:27 PM posted to rec.bicycles.tech
slide
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Posts: 55
Default New Crank Forward - First Impressions

landotter wrote:
On Nov 23, 10:23 am, slide wrote:

The only real dislike I have for the bike is the grupo - specifically
the SRAM X.5 gears. My conventional bikes had Record 10 and Shimano XT.
This grupo doens't shift well and will even shift itself. The twist grip
shifters seem attached to elastic cables. The entire shifting experience
is unsure and unsatisfactory. If I grow to use this bike a lot, I'm
upgrading to XT's.


Different cable pull. You'll want to get x.5 trigger shifters. @$50.

Thx. I'll look into it.
  #3  
Old November 23rd 08, 06:29 PM posted to rec.bicycles.tech
landotter
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Posts: 6,336
Default New Crank Forward - First Impressions

On Nov 23, 10:23*am, slide wrote:

The only real dislike I have for the bike is the grupo - specifically
the SRAM X.5 gears. My conventional bikes had Record 10 and Shimano XT.
This grupo doens't shift well and will even shift itself. The twist grip
shifters seem attached to elastic cables. The entire shifting experience
is unsure and unsatisfactory. If I grow to use this bike a lot, I'm
upgrading to XT's.


Different cable pull. You'll want to get x.5 trigger shifters. @$50.

  #4  
Old November 24th 08, 12:10 PM posted to rec.bicycles.tech
Bernhard Agthe
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Posts: 210
Default New Crank Forward - First Impressions

Hi,

slide wrote:
Due to major back injuries / surgeries, I sold my conventional diamond
frame bikes and bought a Rans CF bike called the Dynamik. This isn't a


Congrats to your new riding experience ;-)

The only real dislike I have for the bike is the grupo - specifically
the SRAM X.5 gears. My conventional bikes had Record 10 and Shimano XT.


OK, X.5 would be comparable to Shimano Deore - personally I have SRAM
X.7 and can only compare it to LX - I like the X.7 way better. SRAM did
some major design changes which lead to actually better shifting
performance: they changed the cable pull ration leading to stronger
springs throughout the mechanism.

Though I don't know X.5, they tend to use better materials for the
"higher" gruppos, so X.5 should basically behave the same as X.7 ;-)

This grupo doens't shift well and will even shift itself. The twist grip
shifters seem attached to elastic cables. The entire shifting experience
is unsure and unsatisfactory. If I grow to use this bike a lot, I'm
upgrading to XT's.


If you try that, you'd have to change your rear mechanics, too. But try
to find out why your actual drive train is not satisfying - check the
attachment points, the cable clamp, etc. It is worth getting the
shifters adjusted right (I usually have my shop do the adjustment and if
I don't like it I do some fine-tuning at home). Personally I do not like
twist grip shift, though on a recumbent you have little options. Trigger
shift may not fit. But if it does, go for SRAM trigger shifters -
they're the best I've ever had! Otherwise, the hardest thing is to get
the adjustment right - but you've done this with XT and Record, too...

By the way, if you want to go up a mountain, try not to pull on the
handlebars. Sit back, lean back, get a slow gear and try to work with
high cadence and little force - takes a while to get used to, but is the
recommended climbing style for anything not mountain-bike or
racing-bike, anyway ;-)

Ciao..

  #5  
Old November 24th 08, 03:44 PM posted to rec.bicycles.tech
slide
external usenet poster
 
Posts: 55
Default New Crank Forward - First Impressions

Bernhard Agthe wrote:


If you try that, you'd have to change your rear mechanics, too. But try
to find out why your actual drive train is not satisfying - check the
attachment points, the cable clamp, etc. It is worth getting the
shifters adjusted right (I usually have my shop do the adjustment and if
I don't like it I do some fine-tuning at home). Personally I do not like
twist grip shift, though on a recumbent you have little options. Trigger
shift may not fit. But if it does, go for SRAM trigger shifters -
they're the best I've ever had! Otherwise, the hardest thing is to get
the adjustment right - but you've done this with XT and Record, too...

By the way, if you want to go up a mountain, try not to pull on the
handlebars. Sit back, lean back, get a slow gear and try to work with
high cadence and little force - takes a while to get used to, but is the
recommended climbing style for anything not mountain-bike or
racing-bike, anyway ;-)


I will surely check things out before replacing anything. Right now I'm
just accepting the lousy shifting figuring it can be fixed even if I'm
unsure just how. I did put the bike on a stand (fixed a flat) and
checked the shifting w/o load. It seemed well adjusted. The problem is
when I'm in the 3-4-5 range the bike will shift itself but not regularly
nor with any fixed input I can determine. Frex, in the past, I've had
bikes maladjusted which will shift when put under load. This auto
shifting doesn't seem tied to any situation I can determine.

It's an annoyance rather than a real hindrance, though.

Also keep in mind that this isn't a recumbent but a CF conventional.
Think of an Electra Townie. I'm supposing that the longer throw to the
rear dérailleur is part of the problem. Also coming off of a Record 10,
I'm probably a bit spoiled in my expectations.
  #6  
Old November 24th 08, 06:01 PM posted to rec.bicycles.tech
Bernhard Agthe
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Posts: 210
Default New Crank Forward - First Impressions

Hi,

slide wrote:
I will surely check things out before replacing anything. Right now I'm
just accepting the lousy shifting figuring it can be fixed even if I'm
unsure just how. I did put the bike on a stand (fixed a flat) and
checked the shifting w/o load. It seemed well adjusted. The problem is
when I'm in the 3-4-5 range the bike will shift itself but not regularly
nor with any fixed input I can determine. Frex, in the past, I've had
bikes maladjusted which will shift when put under load. This auto
shifting doesn't seem tied to any situation I can determine.


Just from a look at the photo, this seems to be cable routing along the
down tube, under the bottom bracket? Just try something: exchange the
cable including the housing of the cable. Route the cable in a
continuous housing from shifter to rear mechanics. You might get rid of
the "ghost shifting" that way, at the cost of more friction in the cable
meaning you'll eat up the extra spring strength quickly - the shifting
will feel really mushy... Don't know exactly what to do... The routing
just seems suspect to feeling mushy due to the extra-long cable...

Also keep in mind that this isn't a recumbent but a CF conventional.
Think of an Electra Townie. I'm supposing that the longer throw to the
rear dérailleur is part of the problem. Also coming off of a Record 10,
I'm probably a bit spoiled in my expectations.


Well, the rear mech works fine by itself, the shifter also, I do suspect
the very long cable run. Ask the tandem users what they do - their
problem is similar...

Have fun!

  #7  
Old November 24th 08, 07:04 PM posted to rec.bicycles.tech
slide
external usenet poster
 
Posts: 55
Default New Crank Forward - First Impressions

Bernhard Agthe wrote:
Hi,

slide wrote:
I will surely check things out before replacing anything. Right now I'm
just accepting the lousy shifting figuring it can be fixed even if I'm
unsure just how. I did put the bike on a stand (fixed a flat) and
checked the shifting w/o load. It seemed well adjusted. The problem is
when I'm in the 3-4-5 range the bike will shift itself but not regularly
nor with any fixed input I can determine. Frex, in the past, I've had
bikes maladjusted which will shift when put under load. This auto
shifting doesn't seem tied to any situation I can determine.


Just from a look at the photo, this seems to be cable routing along the
down tube, under the bottom bracket? Just try something: exchange the
cable including the housing of the cable. Route the cable in a
continuous housing from shifter to rear mechanics. You might get rid of
the "ghost shifting" that way, at the cost of more friction in the cable
meaning you'll eat up the extra spring strength quickly - the shifting
will feel really mushy... Don't know exactly what to do... The routing
just seems suspect to feeling mushy due to the extra-long cable...

Also keep in mind that this isn't a recumbent but a CF conventional.
Think of an Electra Townie. I'm supposing that the longer throw to the
rear dérailleur is part of the problem. Also coming off of a Record 10,
I'm probably a bit spoiled in my expectations.


Well, the rear mech works fine by itself, the shifter also, I do suspect
the very long cable run. Ask the tandem users what they do - their
problem is similar...

Have fun!

Thx for the ideas, Bernhard! I have a friend who has a Dyanmik and also
a tandem. I am going to guess he's addressed this somehow. Being he
worked years at an LBS, he can also do the new routing you suggest
properly where I'm unsure if I can myself.

Just in time too. I got back from a casual ride and during a sprint
across a 6 lane busy street the bike shifted itself tossing me off the
pedals and making for a bit of a pucker until I found the pedals again.

I was pretty darned annoyed.

-paul
  #8  
Old November 25th 08, 07:03 AM posted to rec.bicycles.tech
Tom Sherman[_3_]
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Posts: 425
Default New Crank Forward - First Impressions

"slide" wrote:
Due to major back injuries / surgeries, I sold my conventional diamond
frame bikes and bought a R[ANS] CF bike called the Dynamik. This isn't a
recumbent but rather a 'real' bike but in the form of an Electra Townie.
Supposedly the R[ANS] is as fast and climbs as well as a conventional
bicycle but is more comfortable. Here's a link:

http://www.ransbikes.com/Dynamik07.htm
[...]


And I thought the real bicycles were 'bents!

--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the precipitate.
  #9  
Old November 29th 08, 09:26 AM posted to rec.bicycles.tech
Chris[_12_]
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Posts: 275
Default New Crank Forward - First Impressions

On Nov 24, 10:04*am, slide wrote:
Bernhard Agthe wrote:
Hi,


slide wrote:
I will surely check things out before replacing anything. Right now I'm
just accepting the lousy shifting figuring it can be fixed even if I'm
unsure just how. I did put the bike on a stand (fixed a flat) and
checked the shifting w/o load. It seemed well adjusted. The problem is
when I'm in the 3-4-5 range the bike will shift itself but not regularly
nor with any fixed input I can determine. Frex, in the past, I've had
bikes maladjusted which will shift when put under load. This auto
shifting doesn't seem tied to any situation I can determine.


Just from a look at the photo, this seems to be cable routing along the
down tube, under the bottom bracket? Just try something: exchange the
cable including the housing of the cable. Route the cable in a
continuous housing from shifter to rear mechanics. You might get rid of
the "ghost shifting" that way, at the cost of more friction in the cable
meaning you'll eat up the extra spring strength quickly - the shifting
will feel really mushy... Don't know exactly what to do... The routing
just seems suspect to feeling mushy due to the extra-long cable...


Also keep in mind that this isn't a recumbent but a CF conventional.
Think of an Electra Townie. I'm supposing that the longer throw to the
rear dérailleur is part of the problem. Also coming off of a Record 10,
I'm probably a bit spoiled in my expectations.


Well, the rear mech works fine by itself, the shifter also, I do suspect
the very long cable run. Ask the tandem users what they do - their
problem is similar...


Have fun!


Thx for the ideas, Bernhard! I have a friend who has a Dyanmik and also
a tandem. I am going to guess he's addressed this somehow. Being he
worked years at an LBS, he can also do the new routing you suggest
properly where I'm unsure if I can myself.

Just in time too. I got back from a casual ride and during a sprint
across a 6 lane busy street the bike shifted itself tossing me off the
pedals and making for a bit of a pucker until I found the pedals again.

I was pretty darned annoyed.

-paul- Hide quoted text -

- Show quoted text -


I think you can resolve most of your issues with new cables and
housing. Many bikes shift much better after such maintenance. The big
issue is clean cuts on the housing and using ferrules. Many shops just
cut and install, but there is a huge improvement if you file or grind
the housing ends off square and poke the liner open with a sharp
spoke. At the same time, you can make sure that your routing is as
ideal as possible as Bernhard suggests.

Also, keep in mind that your new bike just has more housing than your
previous bikes probably did, so the shifting will be less crisp than
what you have had in the past.

Chris
  #10  
Old December 1st 08, 01:53 PM posted to rec.bicycles.tech
Bernhard Agthe
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Posts: 210
Default New Crank Forward - First Impressions

Hi,

Chris wrote:
I think you can resolve most of your issues with new cables and
housing. Many bikes shift much better after such maintenance. The big

[...]

Depending on the cable used, you should even go to the pain and grease
the cables before assembly (not on specially surface-treated cables).
There are two considerations: grease makes the world go "round" - it
eases the cable's gliding friction inside the housing - and where
there's grease, there's no water - preventing rust and gunk to clog the
cables. I've seen bikes where the grease was missing from the cables and
they behaved poorly (the same for brake cables).

Also, keep in mind that your new bike just has more housing than your
previous bikes probably did, so the shifting will be less crisp than
what you have had in the past.


Actually I've got hydraulic rim brakes - the rear one is as crisp as the
front one, no matter the different cable length. This is likely due to
the low friction of hydraulic systems. I was wondering if this principle
could be used for shifting as well (and I don't talk about the "5rot"
gruppo ;-) My suggestion is using normal shifters and derailleurs (with
cable actuation) and replace the long run of the cable with small
hydraulic cylinders and a hydraulic tube. Like this: shifter - short
cable - cylinder - long hydraulic run - cylinder - short cable -
derailleur. But I was not able to find any cylinder of sensible size and
prize ;-)

Ciao..

 




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