Author Topic: New convert to the dark side and a question about changing wheel sizes  (Read 1705 times)

Back at the beginning of August, I rode my first long DIY for a while and (unsurprisingly) ended up with very sore hands, neck and backside. On the same ride I’d had a chance encounter with Lightning Phil on his P38, and it clicked in my head that maybe a ‘bent was the route to avoiding the aches and pains from long rides.

I did a bit of research and following standard advice I called Kevin at Dtek and had a nice chat with him. He suggested I drop him an email and he’d get back to me with some dates for a try out session. After a couple of weeks waiting for a response ( I still haven’t had one!), I saw an ancient Orbit Crystal (Speed Ross) that looked nice on the ‘bay, put in an offer and won  :)

Having ridden fixed gear bikes exclusively for the last five or so years, I was now faced with the dual problems of learning to ride the ‘bent and learning to use gears and coast again!  It took a few sessions around the local village hall car park before I was able to start and stop without falling off, and then I figured I was ready to venture out onto the road. The first couple of road rides gave me the fear worse even than when I first started riding fixed! But they were fun too  ;D I’ve now done about half a dozen or so rides and getting a bit more confident; although the longest rides so far have only been around 25km, I’m already as fast as I am on my fixed uprights. I still need to work on turning right from a stop at t-junctions  (especially onto busier roads) and hill starts though!

Anyway, onto my question. The Crystal has a 700c rear wheel and a 451 front.  The front has a 20 x 1 1/8 (451x28) tyre fitted and with there’s less than a cm clearance at the fork crown, so there’s no chance of fitting a bigger tyre (not that there’s much choice in 451 anyway) and/or a front mudguard. Can anyone think of any reasons why it wouldn’t be a good idea to replace the 451 wheel with a 406 wheel which would allow me to fit a tyre in the 35/40mm range and a mudguard? The original canti’s at the front have been replaced with a Sturmey drum brake so if I build that into a 406 wheel there’d be no issue with brake drop or clearance etc.

I’m still planning on getting up to Dtek at some point to see what other options there might be for me down the line  :)


Re: New convert to the dark side and a question about changing wheel sizes
« Reply #1 on: October 02, 2020, 04:38:43 pm »
You say that the 451 tyre is a 28, so going up to 35 or even 40 will still gain you a significant amount of tyre-crown clearance, and that means you are also dropping the axle by about that much, thus changing the geo of the bike. Maybe that's fine, I don't know about how the bike was set up originally, or if the geo matches up with the norm for modern recumbents, but that would be the only concern I would have.

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #2 on: October 02, 2020, 04:44:49 pm »
It’s a 451x28 tyre on there at the moment, which is apparently the original spec for the bike. Replacing it with a 406 wheel with a 35 or 40mm tyre would gain me 10-15mm additional clearance at the crown.

The geometry of the bike is already the strangest I’ve come across - the front forks actually rake backwards- it looks like they’re on wrong as the the canti posts are also at the back, but that is apparently how they were made!

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #3 on: October 02, 2020, 04:51:03 pm »
I should add that I’ve got a spare 406 front wheel that I’ve fitted to check clearance, but it’s for rim brakes so I can’t try it on the road.

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #4 on: October 02, 2020, 04:57:13 pm »
If the old wheel is ~20" diameter then the new one will be ~18.5".
Steeper headset angles and less trail tends to be more twitchy.
But with your setup, how much this drop in the front axle will affect it is ????

I should add that I’ve got a spare 406 front wheel that I’ve fitted to check clearance, but it’s for rim brakes so I can’t try it on the road.
Carpark .........  ;D

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #5 on: October 02, 2020, 05:13:25 pm »
I should add that I’ve got a spare 406 front wheel that I’ve fitted to check clearance, but it’s for rim brakes so I can’t try it on the road.

Can you not ride it round an empty car park or suitable area with your spare front 406 wheel? It’ll soon tell you if the slight change in weight distribution is a problem? Just using the rear brake. Personally I can’t see it being a problem. The P38 has a 700c rear and 406 front in the large frame version I have. Front mudguard essentially unless you want the mucky spray in your face and over the frame.

One problem I can see for Audax is where to fit your luggage given the closeness of the top of the seat to rear wheel.

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #6 on: October 02, 2020, 05:29:42 pm »
Can you not ride it round an empty car park or suitable area with your spare front 406 wheel? It’ll soon tell you if the slight change in weight distribution is a problem? Just using the rear brake. Personally I can’t see it being a problem. The P38 has a 700c rear and 406 front in the large frame version I have. Front mudguard essentially unless you want the mucky spray in your face and over the frame.

One problem I can see for Audax is where to fit your luggage given the closeness of the top of the seat to rear wheel.

Yes I guess it would make sense to take a trip down to the village hall car park for a bit of riding with just a back brake to see how it goes with the 406 wheel. Unfortunately there’s definitely no room for a mudguard with the 451 setup - I tried one of my Moulton mudguards and a kids clip on one and it was just too tight with either. Even with a 40x406 there’s not bags of clearance though it does work.

Regarding luggage, I’ve actually now managed to fit a Tortec rear rack on the bike, so I can use my Carradura rack top bag :thumbsup:

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #7 on: October 02, 2020, 05:37:13 pm »
I’m currently using a 37x406 Panaracer  Pasela on the front. No puncture belt but only a couple of puncture since end of March when I fitted it.  Rides nicely.  I will likely refit the marathon 40x406 some time in November. Got an SR series to try and complete first.

I wondered if a rack would fit with that recline but clearly it does  :thumbsup:

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #8 on: October 02, 2020, 07:13:47 pm »
Any chance of going down to 650B on the back which would probably compensate nearly exactly? 45mm drop on the front and 38mm on the back. 650C would be too small but then there isn't much choice of tyre in the 571 size.

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #9 on: October 02, 2020, 07:52:24 pm »
I’m currently using a 37x406 Panaracer  Pasela on the front. No puncture belt but only a couple of puncture since end of March when I fitted it.  Rides nicely.  I will likely refit the marathon 40x406 some time in November. Got an SR series to try and complete first.

I wondered if a rack would fit with that recline but clearly it does  :thumbsup:
I’ve got a choice of 406 Marathons, Kojaks or Continental Contacts in the 35-40mm range that I’ve used on the Moultons at one time or another. I was also thinking the 40mm Marathon would be a good bet for the winter. That was one of the reasons I’m considering doing this - I’ve got everything I need except spokes already 🙂

The rack was a tight fit. My old Blackburn Mountain would only go in tilted at about 45 degrees but the Tortec has a bit more adjustment so it’s only very slightly canted backwards!


Re: New convert to the dark side and a question about changing wheel sizes
« Reply #10 on: October 02, 2020, 08:08:05 pm »
Any chance of going down to 650B on the back which would probably compensate nearly exactly? 45mm drop on the front and 38mm on the back. 650C would be too small but then there isn't much choice of tyre in the 571 size.

That actually did cross my mind. It would actually work out at 22.5mm drop at the front and 19mm at the back so with a 40mm tyre instead of 28mm up front and a 38mm tyre instead of a 28mm on the rear, it would be almost identical to now.  :thumbsup:

The downside would be cost. As I mentioned above, I already have virtually everything I need for a 406 wheel conversion up front. But I don’t have any parts for a 650b conversion. I’d also need to rethink the rear brake as I don’t think the canti’s would line up with the smaller rim - I could fit a rear drum brake too, but again that’s more expense.  :(


Blodwyn Pig

  • what a nice chap
Re: New convert to the dark side and a question about changing wheel sizes
« Reply #11 on: October 02, 2020, 08:29:01 pm »
@ GavinC, welcome to the dark side btw, getting quite busy over here these days. ( recent convert myself, May 1st )

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #12 on: October 02, 2020, 08:36:43 pm »
@ GavinC, welcome to the dark side btw, getting quite busy over here these days. ( recent convert myself, May 1st )

Thanks  :thumbsup: It’s good isn’t it? I’m actually wondering why it took me so long  ;D

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #13 on: October 02, 2020, 08:46:20 pm »
@ GavinC, welcome to the dark side btw, getting quite busy over here these days. ( recent convert myself, May 1st )

Thanks  :thumbsup: It’s good isn’t it? I’m actually wondering why it took me so long  ;D

We all have that thought.

fd3

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #14 on: October 02, 2020, 11:42:19 pm »
You're doing good being up to speed with the fxed.  I did the same, moving from fixed to laidback, suspension, gears, hydraulic disks...  I find it a nice change, but no way am I as fast on the laidback (despite it being a "speed" machine).
Not convinced there'd be an issue with a cm or so dropping of the BB due to the front wheel, I've seen trike conversions where they've gone from 20 to 26" at the front, just a question of what you get used to.  May get a heavier dose of recumbent butt though.
Strange things are afoot at the circle K.

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #15 on: October 03, 2020, 03:50:17 pm »
You're doing good being up to speed with the fxed.  I did the same, moving from fixed to laidback, suspension, gears, hydraulic disks...  I find it a nice change, but no way am I as fast on the laidback (despite it being a "speed" machine).

In fairness, I’m not that fast on the fixed either, so it wasn’t a massive target to beat!

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #16 on: October 03, 2020, 04:44:24 pm »
So this afternoon, I put the 406 wheel on with a 406x35 Kojak mounted (as I figured that’s the smallest size I would likely use and it would be mostly likely to show up any changes in handling etc) and went for a spin around the village hall car park. The result - with the 15mm increased drop at the front (and about a pound less weight without the drum brake!) I couldn’t tell any difference with the steering or handling at all  ;D

So next job is to get some spokes to build a 406 wheel with the drum brake  :) Thanks for all the feedback :thumbsup:


Re: New convert to the dark side and a question about changing wheel sizes
« Reply #17 on: October 04, 2020, 09:07:14 am »
Looking good 😌

fd3

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #18 on: October 04, 2020, 10:45:55 am »
In fairness, I’m not that fast on the fixed either, so it wasn’t a massive target to beat!
Me neither!  I think that the issue for me was that I was at least faster up the hills than most riders on gears, so on the laidback I am just slower all-round.
Strange things are afoot at the circle K.

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #19 on: October 04, 2020, 08:02:45 pm »
In fairness, I’m not that fast on the fixed either, so it wasn’t a massive target to beat!
Me neither!  I think that the issue for me was that I was at least faster up the hills than most riders on gears, so on the laidback I am just slower all-round.

Symptom of your laid backs suspension and weight. If you want to be faster than your fixed you need to dump the suspension and extra weight that brings. Unless you live in the fens where the weight is neither here nor there.

Kim

  • Timelord
Re: New convert to the dark side and a question about changing wheel sizes
« Reply #20 on: October 04, 2020, 08:17:47 pm »
In fairness, I’m not that fast on the fixed either, so it wasn’t a massive target to beat!
Me neither!  I think that the issue for me was that I was at least faster up the hills than most riders on gears, so on the laidback I am just slower all-round.

Symptom of your laid backs suspension and weight. If you want to be faster than your fixed you need to dump the suspension and extra weight that brings. Unless you live in the fens where the weight is neither here nor there.

Except the extra weight of the suspension often becomes worth it on the way back down.

Depends what sort of riding you're doing, really.
Careful, Kim. Your sarcasm's showing...

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #21 on: October 04, 2020, 09:01:33 pm »
Ace! A new convert. Just wanted to say hi and well done for breaking the biases and group-think.
Cruzbike V2k, S40

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #22 on: January 19, 2021, 10:53:49 am »
Hi Gavin, is it an Orbit Crystal or a Speed Ross, they are not the same.  I got the latter on eBay from a guy in Cornwall some time ago with a 5-spd rear wheel but unfortunately the "celery stick" forks snapped on a descent at 30mph+ not too long after so I got M5 to replace them, if you are concerned about strength.  A wider rear wheel fits into the dropouts if you prise them apart.  All in all a lovely 'touring'-style bike, not very aero compared to others but climbs very well, with a 26 front to 28 rear I can get up anything on it.  I had hardly ridden it for ages as the chain kept snapping on climbs, but then eventually realised a tooth on the smallest front cog had chipped off, and other issues, so now all fixed have been doing a few rides again.  Like you I had been thinking of running a 406 wheel, hence was drawn to your post, and have just received V-brake 451 to 406 convertors in fact, so really interesting to read your feedback, thanks.  When my current Duranos either wear out or fail I'll probably switch down to something wider.  Another thing I did was replace the absolutely rubbish "plastic pram wheel" idler with something from Terracycle, you'll find it can bolt into the same hole, if it's the same as mine (hopefully not!).

Re: New convert to the dark side and a question about changing wheel sizes
« Reply #23 on: January 20, 2021, 09:16:37 am »
Hi Jon, mine is an Orbit Crystal. From the research I’ve done, I think the Speed Ross/Crystal design was constantly evolving and there were several iterations of it along the way. They do share the same DNA though. Mine came with a 135mm spaced 7 speed rear wheel and from a 1997 review I’ve read, I believe that was the original setup. It also has a pretty cheap and nasty plastic idler, though it seems to do the job. What Terracycle idler did you replace yours with?

I agree it climbs well - since buying the bike, I’ve had a chance to try a couple of more modern recumbents and they both felt far less agile uphill. That may have been down to my relative lack of experience riding the bikes in question though. I also had it in my head that since the Orbit was an old design, the ride would be less refined generally compared to more recent ‘bents but I haven’t found that to be the case either  :thumbsup:

I did change the front wheel to 406 size, which enabled me to fit a 40mm Marathon tyre and mudguard to the bike. Since doing so, I’ve ridden around 200km on the bike, including a 100km brevet at the end of last year, with no problems. It rides pretty much the same as with the 451 wheel IMO. My bike is fitted with a front drum brake so I didn’t have to worry about the canti brake position.


Re: New convert to the dark side and a question about changing wheel sizes
« Reply #24 on: January 20, 2021, 06:22:13 pm »
Looks great! :-)  Yes the idler looks identical, I have been looking for details of my upgrade and have emailed the guy from Icletta, hopefully they still do it but one of the links is dead, I'll let you know.  The problem was that the chain cut a groove in the idler over time, when the chain kept snapping I assumed it was because the idler was twisting it via this groove before feeding it onto the chainring, hence replaced it (only not for it to fix the problem).  Was riding mine today and thinking I could cope with the front wheel slightly lower, if you look at the M5 models there is a City Racer and City Cruiser (I think), one with 451 and other with 406, I can't believe the frame is any different.  One advantage of getting a replacement fork from them was the brake bosses are now on the rear, so I could put decent V-brakes on.