Friday, June 23, 2017

My recent velomobile issues and solutions


My recent velomobile issues and solutions
My recent posts on velomobile efficiency appear to have been well received.  There were numerous comments and debate on several points.  I think that there is room for the type of general information to let people better understand velomobiles, as well as I observe as it relates to velomobiles including the technology, racing and commercial aspects.  Looking at the subject I have touched on in the past, I think that I have covered a many subjects but I’m still looking for new subjects to address and I’m open to suggestions.

While I’m writing this, outside the velomobile world, I’m also very busy with other activities and I may not be able to post as often as I would like.  This also affected my riding, in addition to renovation work underway, the weather, large flooding throughout the region and a bumper crop of biting insects has made difficult to ride.

I had a few other setbacks on the velomobile front.  I wanted to get new tires for my velomobile.  I wanted to convert a set of narrow wheels for tubeless while keeping my regular wheels for general riding and brevets because the road conditions are not so good especially in the spring.  I purchased a set of Schwalbe Pro One for the front and a Schwalbe One for the rear from Schwalbe North America as no distributors in Canada had the tires available.  The Schwalbe One tire was not available in size 28-406 in North America so I ordered the 28-406 from Europe and placed another order for matching tubes.  A few days after the order, I received a message from Bike 24 that the tires are in back order with no delivery date.  So I cancelled and placed my order with Ginkgo where stock was apparently available.  I received the tires but they were Pro-one instead, the company decided to upgrade me since they too had no stock.  I was a bit disappointed since I wanted to compare the two versions.  Meanwhile, the latex tubes sent before were no show and after a few more weeks, the package was lost I contacted Ginkgo and they sent me another set of tubes. 

During some maintenance after a brevet I realised that my wheels needed to be trued.  I removed the wheels and took them to a local bike mechanic.  When the wheels came back, the mechanic informed me that two of the rims had a few cracks around the spokes.  I looked at my options and decided to buy a new set of wheels with ventilated hubs as I have had a few close calls after long descents and these may help keep the brakes cooler.  I also bought new rims, spokes and  bearings to replace those on my existing wheels leaving me with a set of spare wheels.

While I had the wheels off, I proceeded to change the L-bracket that holds the steering and suspension.  I mentioned some time ago that the brackets were upgraded to calm the twitchy steering of the early DF and DF-XL.  The new brackets change the steering geometry somewhat. 
 
The old and the new notice the position of the two smaller hole in the middle
The process was fairly quick but I needed to perform an alignment after this.  I used the method developed by Charles Snyder and published on BROL.  I could not get reliable readings in large part because the wheel covers… well cover the rims.  It is hard to see if they are perfectly aligned.  I tried my best to make the measurements but when I went for a ride with the new tires, the velomobile did not feel right, it was pulling to the side and my average speed was reduced by approximately 8km/h.  I needed to do something to fix this.  I looked at other ways to perform the alignment and decided that it would not be too hard to build a new jig that is much more accurate.

Using 5/16in T-Slot tracks, 4in L-bars and some 1/4in bolts, I made two accurate jigs that measure the wheel spacing at the front and rear simultaneously. It did not take too long after I gathered all the parts.
Overall view of the new tool

Close-up on L-brackets


I took my new tool and proceeded to perform an alignment.  I had marked the middle of the tool as a reference to align with the middle of the velomobile.  I used my laser level to find, mark and align the tool and velomobile.  I had placed the brackets on each side 70cm apart but I found that when the middle was aligned, the brackets on the right side of the velomobile were touching the wheels while the left side was about 3cm away from the wheels.  I could not understand what was going on.
The left and right sides do not match

I suspected that the shell was not symmetrical so I checked with PeterB who had performed a few alignments on his DF and with Ymte and they confirmed that the shell is not symmetrical.  This is important for those of you who will want to perform a wheel alignment on a velomobile.

Performing the alignment
After this I performed the alignment without taking into consideration the symmetry.  I was able to get 1.7mm toe-in and took the DF for a ride, my first ride in a few weeks with the new tires (with regular tubes), alignment and the new L-bracket.  I’m happy to report that the steering has improved, the velomobile is much more predictable but there was a significant speed improvement.  Even with my lack of riding, I was able to come close to the best results I posted a few years ago on the same route.  I hope to be riding more in the next few weeks and hopefully improve on those results.

Visit to the heartland
I am currently planning a visit to Europe and the Netherlands in the fall (September-October) and will take the opportunity to meet with velomobile manufacturers and riders.  I hope to be able to see new velomobiles, discuss with those involved about the opportunity and challenges for velomobiles as well as learning from what is done in their enronment.  I should attend the race at the Dykes on October 15th.  Please let me know if there are any opportunity to meet.

Trisled

The Australian manufacturer appears to be embracing 4-wheel velomobiles.  After the success of the 4-wheel tandem velomobile, braking the tandem 24 hour distance record, the company announced what is probably the first Australian PedalPrix 4-wheel velomobile.  There are few details released but the new velomobile will be tested at the next PedalPrix race.  Here is what we know so far: Completely new chassis design with absolutely no main tube, radical new drive system Ben has been working on for 20 years,  Some comments seem to indicate that the drivetrain may propel the left wheel, this would be similar to the DF-4.  The designers paid special attention to the aerodynamics in the design and the velomobile was completely CAD modeled and CFD tested.  The 4-wheel design should provide safety and stability of four wheels! In the rough and tumble world of PedalPrix racing.

InterCityBike

ICB is apparently designing a foam panel to close the area around the rear swing arm and should be available soon. While it is best to use a bag for small items., this panel is designed to contain loose items from traveling to the rear derailleur compartment.  The cover will be attached to the shelf, reinforcement rib and chain cover with Velcro fasteners. There will still be some small openings such as around the inner swing arm mount and the chain tunnel. ICB is not ready for orders yet so don't start ordering them immediately, there will be an official announcement on the website.. That's why the velomobile bag is provided.

WHPVA World Championships

The championships were recently held in Mannhein Germany with participants from several European countries.  Velomobiles took the first places in all events even ahead of Beano the Streamliner (2 wheels).   There is a bit of controversy regarding the event, maybe there is room for improvement for the next WC.
Results for the WC2017:
1 hour airport crit: http://www.hpv-wm-2017.de/index.…/…/ergebnisse-de/41-1-hour…
333m velodrome flying lap: http://www.hpv-wm-2017.de/…/en/ergebnisse…/38-333-3m-sprint…
1km velodrome standing start: http://www.hpv-wm-2017.de/…/ergebnisse-de/40-1-000-m-sprint…
3 Hour city centre crit: http://www.hpv-wm-2017.de/index.…/…/ergebnisse-de/42-3-hour…
Pictures https://www.wjst.de/images/pretty/central/2017HPVWMMannhein/

4 comments:

  1. Did you add any weight to the DF for the toe-in measurements?

    ReplyDelete
    Replies
    1. Good question, I did not add weight. I looked at several methods and not everyone is adding weight, for example, the Velomobiel.nl manual for the Quest does not mention this in their procedure.

      Delete
    2. Good to know. I think that it doesn't matter as long as we remain consistent in our measurements and testing. Thanks for sharing your experiences.

      Delete
  2. Very informative post again, thanks for that. I intend to join the LEL in the fall too, hope to meet you.

    Best regards,
    Henk-Jan

    ReplyDelete