Author Topic: 2010 Novara Randonee - Slack Head Tube Angle  (Read 8363 times)

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Offline mkwdrs

2010 Novara Randonee - Slack Head Tube Angle
« on: March 26, 2010, 09:07:03 am »
I am considering purchasing a 2010 Randonee.  I noticed that the geometry has changed since from the 2009 Randonee.  It seems the 2010 has a slacker head tube angle and a shorter top tube.  Due to the slacker head tube (I think the fork rake is the same), how will the 2010 bike handle compared to the 2009 model?

Offline waynemyer

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Re: 2010 Novara Randonee - Slack Head Tube Angle
« Reply #1 on: March 26, 2010, 01:31:47 pm »
Bicycle handling is a very complex system.  But all other factors being equal (impossible), a slacker head angle will result in a slower turning bicycle.  This generally translates to less responsive, more stable at slower speeds, and requiring more lean in order to get the bike to turn.
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Offline Tourista829

Re: 2010 Novara Randonee - Slack Head Tube Angle
« Reply #2 on: March 26, 2010, 03:30:33 pm »
I could not find the geometry for 2009 vs 2010 Novara Randonee Touring Bike. Can you get a list of specs that shows the size bike you would fit. Like most things in life, a change in one area may have an effect on another. I know a lot of people who rely too heavily on specs and fail to just get on the bike and ride it. (In multiple configurations) Due to the lack of available product, most never get a chance to try many bikes, they end up riding one bike or have to order a bike unseen. This is sad. Most touring bikes have angles for a more relaxed ride, stability with bags, longer chain stays and a longer overall wheelbase. The down side is one gives up a little in the handling, but a more comfortable ride. They also come with a slight weight penalty. Check for frame flex out of saddle and descents. (too bad you can't test ride it with full gear) I might change the granny gear out from a 30 to a 24. Overall it all boils down to your mission. REI sells a lot of them and the price is right.

Offline digimarket

Re: 2010 Novara Randonee - Slack Head Tube Angle
« Reply #3 on: July 26, 2010, 05:11:56 pm »
Bicycle handling is a very complex system.  But all other factors being equal (impossible), a slacker head angle will result in a slower turning bicycle.  This generally translates to less responsive, more stable at slower speeds, and requiring more lean in order to get the bike to turn.

The trail dimension of a bicycle is much more closely related to the turning speed and handling than is the head angle.  You can achieve fast or slow steering with nearly any head angle depending on how you modify the trail with the fork offset. Slack angles have advantages for touring bikes because they allow for more toe-clip/fender clearance without a longer top tube.  It also makes for more bump absorption with the slightly more inclined angle and the ability to make an effectively longer fork with a bit more curve (offset) in it without decreasing the trail too much.  The reason it isn't used on racing bicycles is they are made to be as light and short as possible - at the expense of load carrying and comfort.

There are a lot of factors that are important in geometry and handling for loaded touring bikes.  I haven't seen the 2010 specs yet, but I was just looking at the specs for a slightly older Randonee - and they weren't what I would want in a loaded touring bike.  The key spec was a 72 degree head tube angle (good for touring) and a 55mm offset fork.  While this is "traditional" relaxed touring geometry - it is also low trail because of the relatively large offset - and will require  more steering input to intitialize (and then counter) turning.  This "slow" steering is considered a plus on touring bikes with floppy/heavy handlebar bags and tired riders because the front end can wiggle around without much impact on the direction the bike is headed.  People refer to this as "stable" handling - I consider it unneccesarily slow and clunky. 

Get rid of the handlbar bag (or use a really small light one firmly attached and supported).  Get about half of the weight out of the rear panniers and into front low riders so the weight distribution of the bike is kept balanced (bonus you won't break rear spokes).  Front lowriders put the center of mass of your front load centered on the steering axis for minimum impact on dynamic steering.  Now you don't need slow steering front geometry and you can use a 72 angle and 45mm offset fork.   With your load balanced and your nice big tires properly inflated for the actual weight on them (10-20 pounds less in the front) you will be able to carve corners confidently loaded or unloaded.

The other specs that seemed wrong on the older frames included short wheelbase - a touring bike needs to be stretched out much more than a typical road bike for a number of very good reasons.  Starting with the rear chainstays - longer means the panniers and cantilevers can be a bit further back for heel clearance, but it also moves the center of gravity forward (because the rear axle is further back).  Since the biggest problem with louded touring bikes is balancing the load front and back (for handling and to avoid breaking spokes) this is a big plus.  A longer chainrun also helps on chain angle - allowing you to use more gear combinations with less wear. 

On the other end of the bike - the front center should be longer - so your comfortable touring shoes in their toe clip cage don't hit your fenders in slow speed turns.  60cm front center is the minimum for fender/cleat clearance with 27/700c and fat tires.  Combined with a rear stay as long as you can find (OVER 45cm for loaded touring) this makes for a wheelbase of 105+cm for medium to tall riders (short riders can get by with a bit less). 

In the middle is the top tube length.  All else held constant - a longer top tube makes for a longer wheelbase and more toe clip/fender clearance.  But a rider with a short torso/arm combination, could have problems getting a short enough stem if the top tube is too long.  Frames designed for touring sometimes have relatively short top tubes (relative to the length of the seat tube) with the thinking being that tourers ride in a more upright position (requiring less combined toptube/stem,handlebar reach) Some vintage touring frames had generous top tube length with the goal being toe clip clearance and shorter stems to reduce the negative effects of those floppy handlebar bags.

Basically the older Randonee geometry was way too short to be considered a proper loaded touring design and it had the slow front end steering geometry that I feel is obsolete.  If they lengthened the wheelbase and went to a 71 degree head angle with the same 55mm fork offset - I would say that would all be to the good for loaded touring and handling.  It also had relatively high standover heights for the size of the frames - which might indicate the bottom bracket was higher than it needed to be.

If you look at the very popular Surley LHT you will see that the front end geometry is quicker steering than the older Randonees and the chainstays are much longer.  Even the LHT isn't the full-on expedition geometry ideal for dirt road and long-distance unsupported touring in rough country, but it is perfect for relatively fast loaded touring primarily on pavement and will do very well on dirt roads with the right tires.

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