Sunday, 16 January 2011

Finishing maintenance that I started last week

After last week's service, today I got around to finishing the job.

There is a universal joint in the steering column. It's made with a plastic block which provides a low friction and low weight method building a universal joint, but it's a part which wears over time and introduces a bit of play. In my Mango there was now a bit too much play, so it was time to replace this part.

It's very easy to do. You just take out the two bolts which hold it in place, remove one block and put the other in its place. However, I thought I'd take a few photos to show what happens to the block.

The photos show the old and new blocks next to each other.

By the time I took mine out, the play was really a bit much. I should have done this a while ago. However, you can see that there was no danger of the steering column actually coming off. I don't think it's possible for it to get to that stage.

The play comes not because the holes in the block wear larger, but due to the sides wearing down so that they are no longer flat. They rub against the aluminium of the steering column, which is harder than this plastic block, so it is just the replaceable block which wears out.

I also went on the huneliggers ride this morning. Peter and Harry were waiting at the start point and the three of us set off together in our Mangos through the Drents countryside.

This particular path is new and it was the first time we'd ridden along it. Lovely smooth concrete for cycling through a very pretty area of countryside. It'll be a part of this year's cycling holiday routes.

One of the recreational paths that we used was a bit soft. It's got an environmentally sensitive surface, which is fair enough for what it is and where it is - through a large heath area.

Normally this surface works well enough. However, after a lot of rain and a few freeze and thaw cycles it was so soft that our tyres sank into it a bit and made it rather nasty to ride on. A couple of km of this reduced our average speeds somewhat, but this is a touring ride, not a race, and the scenery is lovely here.

Peter got a puncture in his rear tyre, which gives an opportunity to write about repairing punctures on a Mango. Happily it doesn't take long to sort this problem out. You just find somewhere soft that you can roll the Mango on its side without damage, and take off the tyre and inner tube.

This can be done without having to take the wheel out, as all three wheels on a Mango are mounted on one side only, whichever gearing option you have.

Note also that the chain cannot be seen. It's safely within the bike, and stays clean. Because of this, you don't get oily hands when doing this job, either.

I'd done the same with mine before leaving home. As you can see, there's no snow and ice today, so I'd swapped back to my extremely puncture proof Schwalbe Marathon Plus rear tyre. I like these in wet conditions because I've never ever had a puncture with them.

In the Netherlands, the main cause of punctures seems to be this sort of small and sharp stone. Peter has a Schwalbe Marathon Racer on his rear wheel. It's relatively puncture resistant for a fast tyre, but it wasn't quite enough against this particular stone. I like Marathon Racers, but for me they're a summer tyre.
Read my review of the Sinner Mango Velomobile.

11 comments:

Pjotr320 said...

It was a fun little ride, just under 60km. The three of us make a fast group of velonauts, more specific Mangoteers, that ride the cycle paths in style.

About the tire: It's my 2nd puncture in 3700km. The 1st one was 200km ago. It's a nice tire, rolls good, enough grip, mounts easy, puncture resistant enough, comfortable.

David Hembrow said...

It was indeed great fun.

All tyres are a compromise in one way or another. Some combination of: Speed vs. grip vs. durability vs. ride quality vs. puncture proofness.

I like the Marathon Racer and wouldn't want to give the impression that it's bad, as it's not. Either yours is a little worn now, or it's just bad luck.

Pjotr320 said...

@David
I know that, and you know that. But it's good that we explain such things to readers ;-)

And true, what a fiddling it would have been if we had to dismount the wheel out of a dirty wheel arch.

Long live single mounted wheels. Finding the cause of the leak takes more time than taking the tire of, and putting it back on.

Neil said...

What are the two black bits near the front? Are they holes for your feet for reversing? Or something else?

And just curious to see the other 2 wearing helmets. Given you say they are not common in NL - is this more common amongst velomobiles or just your 2 freinds happen to wear them?

David Hembrow said...

Neil: Yes, there are two foot holes. You use them to reverse and also they allow air in. Peter has made an aerodynamic adaption to his foot holes.

Helmets are quite often worn by sporty cyclists. You'll often see people with the whole replica team strip, for example, including the helmet.

However, you won't see them on "normal" people riding to the shops, to work or whatever. That group is much larger than the sporty group.

Micheal Blue said...

I realized that as beautiful as the velomobiles are, they are suited for flat terrain. In hilly terrain hauling the extra 16 kg of weight could be a problem. Your country is the ideal velomobile land.

David Hembrow said...

Michael: A 16 kg difference ? That grey and white Mango Sport in the photo weighs just 26.5 kg. If you currently ride a bike which weighs only 10 kg including panniers, lights, mudguards, water proof clothing etc. (remember that a velomobile includes these things) then there is a 16 kg difference.

A velomobile will be slower than a lighter bike up hills, but probably not as much as you think. If you weigh 80 kg and you ride an 11 kg bike, vs a 27 kg bike then the difference as a percentage of total weight is only 17% ((80+27)/(80+11)). You just need one or two lower gears.

A long grind up a steep hill is obviously going to be slower, but you have an advantage in rolling hills and of course long downhills go all your way.

jonbendtsen said...

In shorts! :-O what kind of sunny warm weather do you have there south of Denmark?

Paul Martin said...

Great post - my user manual will have all these blog posts added to it, thanks David!

I was going to respond to Michael Blue's comment about the hills but I see that you have already - and included my little film :)

I am surprised at how easy hills are in the Mango - I thought it would be a struggle but it isn't. Not having to worry about balancing also seems to make it easier and I can generate considerably more force in the recumbent position - at least, that's what it feels like.

Most of those roads in that film were flooded this week but things are slowly getting back to normal here. I'm itching to go for a ride in my Mango tomorrow - I'm having withdrawal symptoms!

No punctures yet, touch wood.

David Hembrow said...

Paul: Good to hear from you again. I assume there's a lot of work to do in Brisbane, and I wasn't sure you'd have time for posting comments.

Paul Martin said...

David: Thank you. Our ground floor flooded (garage) but we managed to move all bicycles to higher ground, including the Mango. Thank goodness it fits through a standard doorway and is so light!

We were very lucky - some neighbouring houses will have to be demolished but thankfully nobody in our area was injured or killed.

We've spent some time helping clean neighbouring properties but it will take weeks before Brisbane looks vaguely normal again. It has brought out the best of humanity - I'm not nationalistic about such matters, unlike much of the media - any human would do the same regardless of race, background or country of residence/birth. It's called being human and it was lovely to see...

Kind regards,