A simpler Silvio?

[Kavman]

Hi,

I'm just going to throw this out there, something I wrote last year regarding the Sofrider:

I'd love to see a replacement for the Sofrider which has no suspension, but has room for lower pressure, wide tires (42 - 55 mm) and full fenders. Jan Heine and Bicycle Quarterly are pretty effectively showing that wide tires with supple sidewalls can be even faster, and safer, than narrow, high pressure tires in most situations. The bike would be simpler and have a traditional rear rack. It would have seat braces and an adjustable seat angle. I wonder whether such a bike could be built for a similar price to the Sofrider.

But what do I know? I've never ever ridden a Cruzbike! I just like what I'm seeing from the company.

Rereading this, I guess what I'm really hoping for is a relatively simple MBB bike with the Silvio seat angle and room for wide tires, no suspension, room for full fenders, etc. True, I've only just sat on a Cruzbike once, a Vendetta, but I've ridden recumbents for 17 years and currently have three of them. I'd love to have something like the Silvio, but I just don't like how it is so limited in its tire sizes and don't see it as the touring machine it's meant to be. I guess I'm envisioning the Cruzbike version of a randonneuring bike. (I'm having trouble posting a link: Just Google Jan Heine's Off the Beaten Track and have a look.)

The speeds these randonneuring bikes can go with strong riders is amazing.

Anyway, food for thought.

Kevin

 

[castlerobber]

I've never ever ridden a Cruzbike!

I've only just sat on a Cruzbike once, a Vendetta

Maybe it's time to at least try one out? You might find that the Silvio is what you're looking for after all.

I guess what I'm really hoping for is a relatively simple MBB bike with the Silvio seat angle and room for wide tires, no suspension, room for full fenders, etc.

Assuming you're truly interested in a rando Cruzbike, and aren't just idly speculating:

Consider the QX100. No front suspension. It'll take 26" tires up to 2" wide. Not wide enough? Put 24" (507) wheels on, and you should be able to fit that 55 mm tire and a fender.

Don't like the rear suspension? Adjust or replace the shock, like this forum member did: Quest on AIR

Want the seat angle more Silvio-like? Flip the seatpost over, or replace it. IIRC, some have gotten the seat angle on a Quest or Sofrider down below 30 degrees.

Decent rear rack? There are a couple of new options, at least one of which holds 50 lbs.

Now, is Cruzbike going to offer a stock bike set up like this anytime soon? I don't imagine so, and certainly not for $1000 or $1200 like the old Sofrider or V2/K.

I'm having trouble posting a link

The spammers have been running rampant. I believe there's a minimum post count now before links are allowed.

 

[Kavman]

Thanks for your reply, Castlerobber. I guess part of my problem is that I'm so far away from anyone who has a Cruzbike to try. Maybe you're right: a QX100 may be more bike than I'll ever need. And, yes, I'd be the first to admit that I'm never going to be a randonneur, putting 100's of km on a bike over a weekend or something. I'm more of a commuter than anything else. On the other hand, a randonneuring bike is really just an excellent all-round bike, even if you're just going 20 km each day.

I just would like to have a simpler bike (not a cheap bike, mind you, as I don't mind spending money on quality), one with suspension in the tires themselves and able to fit decent fenders. The roads are rough where I live and winter is months of rain. But I like to travel efficiently, sometimes laid back a fair bit, and I just wonder whether the Sofrider and Quest-style frames unnecessarily complicate the seat adjustment, not to mention the attachment of a rack. Also, I've got to say that I've never taken to the look of the Quest-style frame.

I guess I'm imagining something with the Silvio's front end and boom, but with a non-hydroformed, tubular frame, and more clearance for the tires. The Silvio and Vendetta frames are beautiful things, but more engineering than I need.

Kevin

 

[MrSteve]

Before the new-to-me Vendetta showed up, I'd been riding my Sofrider V1 for about seven years.
Over the years, I modified the Sofrider for extra speed ... and you know what?
On flat, level ground, my hot-rodded Sofrider is every bit as fast as the Vendetta.
So, there is speed potential in the old QX100 design.

To get that speed out of the Sofrider

, though, was kind of involved:
- custom built seat, reclined at eighteen degrees;
- narrow drop handlebar;
- skinny rear wheel with wheel covers;
- high-pressure slick tires;
- custom chainstay;
- wide-range transmission: 11-52 high gear to 23-34 ultra-low gear, triple-ring front.

The Vendetta climbs like my Sofrider is dragging an anchor and it has a much
higher top speed... other than those two performance advantages, the Vendetta is as fast as my Sofrider!

 

[Tuloose]

I'm with you on that line of thinking Kavman.
I have often thought there should be room in the Cruzbike stable for a true touring machine.
Something like the QX100 but without the rear shock.
This would allow for a rigid rear rack to be attached to the frame.
A rear shock is not needed in any case, at least for travel on paved roads.
I don't know why CB continues to spec the Sofrider, QX100 and Quest with a shock although I do enjoy the minimal amount of front & rear dampening on my Silvio.

 

[1happyreader]

traditional rear rack

but without the rear shock.
This would allow for a rigid rear rack to be attached to the frame

I gotta quibble here, the front of the standard rack CAN be attached to the current frames.
The Sofrider has both a lower shock mount and the V-brake nuts that would secure the front non suspended rear rack to the frame.
The quest bikes have at very least the lower shock mount.
I am thinking about stealing this rack and mounting it on my sofrider instead of using it as a fender . Centering it above the axle w/o the funky triangles. No seatpost required.

 

[Kavman]

Mr. Steve: I've admired your zooped up Sofrider before. It did get me thinking about the possibility of getting a used Sofrider and seeing what I could manage with it. My hope remains, however, that Cruzbike will do the hard work for me and offer much the machine I was asking about.

Tuloose: So I'm not alone in my thinking! I was also wondering whether a tubular frame might allow for people to use a variety of seats. Not that there's anything wrong with the Cruzbike seat, but people might have preferences.

Oh, and I wonder whether a rigid rear end might make it easier to fit the bike to the TTrike attachment. Just wondering.

 

[MrSteve]

About the rear shock:

The stock wheel dampers sort of work, kind of, when you compare them to more efficient, effective, adjustable, aftermarket air shocks... but the air shocks are shockingly expensive.
When I want to sprint as fast as possible, I remove the rear shock and replace it with a 1" one inch) diameter hardwood dowel.
This turns the bike into a hard tail.
It would not be very difficult to make the hardtail modification permanent... a little resin to seal the wood, to protect the mounting holes and a little paint to shield the resin and, Bob's-your-uncle.
My point is, it's really simple to morph a Cruzbike rear suspension to a hardtail.

About adjustable seats:
A good adjustable seat has two inherent disadvantages... they tend to weigh more than standard seats and there are moving parts to worry about.
The best adjustable seats are beautiful and are usually found on expensive, hand made European models.

 

[Kavman]

MrSteve: Yes, you're right, I could buy a second-hand Sofrider and eliminate the rear suspension, or pick up an air shock to increase the pedaling efficiency. I'm willing to bet that this is what I'll end up doing, should one be found close enough to me to go try out. (I've been looking.) But this would not give me the Silvio front end, and that's what I think I'm ultimately hoping for. Not enough, however, to buy a Silvio, since this would be thousands for a bike that still isn't what I'm after.

Could Cruzbike offer the bike I'm talking about for a price comparable to a Bacchetta Giro or a RANS Stratus? Better yet, would it be possible to sell a frame set? I know that I'm no businessman and haven't the foggiest clue about what it takes to get a design to market, but I'm asking for less, not more. (Except for the tire clearance part.)

 

[ratz]

MrSteve: Yes, you're right, I could buy a second-hand Sofrider and eliminate the rear suspension, or pick up an air shock to increase the pedaling efficiency. I'm willing to bet that this is what I'll end up doing, should one be found close enough to me to go try out. (I've been looking.) But this would not give me the Silvio front end, and that's what I think I'm ultimately hoping for. Not enough, however, to buy a Silvio, since this would be thousands for a bike that still isn't what I'm after.

Could Cruzbike offer the bike I'm talking about for a price comparable to a Bacchetta Giro or a RANS Stratus? Better yet, would it be possible to sell a frame set? I know that I'm no businessman and haven't the foggiest clue about what it takes to get a design to market, but I'm asking for less, not more. (Except for the tire clearance part.)

I'm going to do a brain dump here and add more data to the discussion without really solving your goal but hopefully will give more info to consider.

Qx100 is your best bet today;

[x] wide tires
[x] Really wide tires if you go for smaller wheels
[x] fenders (Front easy; rear use a mtb style, or arm mounted)
[x] adjust able seat over a pretty wide range
[x] Near hard tail (just crank the preload on the spring shock to the max)
​

Right there you can get it pretty close to what you want very fast for a good price. Thats not likely to change soon.

In my opinion you won't get the Silvio boom layout until the external bearing cup clamps are phased out. That change will have to happen eventually because 24mm spindle cranks are fading out in the racing gear levels, more and more bikes are going press-fit Bottom brackets and 30mm spindles. So eventually there will be nothing to clamp to. Therefore that front end will have to be redesigned to be stiff, light and clamp free. When that happens 1 boom design could potentially be used across the entire line of bike; instead of 2. Is that advantageous? Maybe but we can't be certain. While it's certain to happen it's also probably a year or two out (Purely speculation I have no info).

The Q boom is clamp free but it's not an inheretly light or stiff designed in the race bike sense. Because the current Q series is clamp-less it has access to much less expensive cranksets in the square tapper form factor. So to keep costs down on the budget line of bikes you can't really drop in a boom that require expensive cranks.

So for now they have two designs one that requires outboard bearings and that that can handle square taper.

Next up are Rake and Trail. They complicate things for the fork; you can't just swap forks and chain stays out between frame if you do the handling can get very squirrelly. The geometries are what they are to get the desired handling characteristics For this reason you could say take a Vendetta V20 132mm fork and put it on an older Vendetta 2.o (yellow) The bike won't handle right. The forks are also very likely custom units that have to be built in volume; no other high volume bike needs a 132mm width on the front fork, so evolution is going to be slow. Simple change can complicate that evolution If you want wide tire the fork as to be wide. But how do you ensure thigh clearance at the top of the fork without making the bike really tall? A Cruzbike Fat bike would be cool but it would require a-lot of reengineering to the fork; and bike height so that you could still pedal it. Sucks but it's complicated.

Lastly don't forget the lateral forces that fork on a Front wheel drive has to withstand. Basically the fork has to be perfect or you get sued out of business when it fails. Homebuilt bike threads are really cool to read and the usually all have one thing in come. The builders tend to reusing or welding on to stock forks. Almost no one tries to make there own alluminum or carbon forks because it's really hard to do. Function dictates form; and custom means lost of $$$$$

That's wordy way of saying don't wait; start modifying and enjoy something really close.

Parting thought. Don't let the Q style fool you; it's no slouch; I rode a customize Q version 2 (affectionately know as the Quickr ) with the 425 little wheels last summer at a 100 mile event. I ran 28mm duranos with moderate pressure and I left my shock pretty loose and springy for comfort. On that ride, Up hill, into the wind, (gosh sounds like a speech I give my kids) it took 8 miles for a pace line of Diamond frames to catch me; and they had to burn through 6-7 lead out riders to do it.(Q100 didn't exist when I built it). Mine has a front shock from the old days so it's not even as quick as the Q100 would be.

Also don't be afraid to have Robert quote you a custom Qx100 build with smaller fat tires; they don't always have to be stock builds.

 

[castlerobber]

Thanks for your reply, Castlerobber. I guess part of my problem is that I'm so far away from anyone who has a Cruzbike to try.

I bought my Q451 (same basic frame as the Q559 or QX100, but with front suspension and smaller wheels) without ever having seen a Cruzbike in person. I was determined that I was going to learn to ride it; but if I couldn't, there was that 30-day return period, with a reasonable restocking fee. Didn't know until a couple of months later that there was a fellow Cruzbiker living just one county over, a friend of one of my coworkers.

I've modded my Q just recently with 24" wheels, 1.5" tires, and an air shock. I'm super pleased with the results. Quest 451 to 507

As far as wider tires, this BROL member did the 24" wheel mod awhile back; he says, "I have a 2" (51-507) on the front & a 2.3" (58-507) on the rear." http://www.bentrideronline.com/messageboard/showpost.php?p=1273062&postcount=1

Also, I've got to say that I've never taken to the look of the Quest-style frame.

Yeah, it is a little different, but it's grown on me. At least with the QX100, there are color options.

 

[quickbeam]

Because the current Q series is clamp-less it has access to much less expensive cranksets in the square tapper form factor. So to keep costs down on the budget line of bikes you can't really drop in a boom that require expensive cranks.

I'm probably the least knowledgeable person here on bike parts and such, but is that a main reason for the large price difference between the Q series and the Silvio/Vendetta? Either you pay under $2K or over $4k, nothing in between.

 

[JOSEPHWEISSERT]

I'm probably the least knowledgeable person here on bike parts and such, but is that a main reason for the large price difference between the Q series and the Silvio/Vendetta? Either you pay under $2K or over $4k, nothing in between.

Would you rather have $4,000 in your pocket or happiness between your legs? Specifically, a Vendetta between your legs - not what you're probably thinking!

 

[Kavman]

Ratz: Thanks for the detailed response. In particular, I really appreciate the info about the BB issue. I'll have to reread what you've said and take a closer look at the bikes themselves. I've got a garage full of bikes and not one has external bearings. If I'm reading the problem correctly, it seems that the wider spindles being used by racers must increase the Q-factor (tread) of the bike? Seems counter-productive. I'll have to research that.

Re. rake and trail: I guess I've been imagining a new frame design with appropriate head tube angle, designed to accept a boom set up like the one on the Silvio. So it's not possible to simply change only the boom set up (so that it would continue straight through toward the rider and not have a stem rising upward) and retain the Q-series fork and chain stays? Now that I think about it, can't you take a Q bike and somehow just extend the boom toward the rider, just like a Silvio? A matter of clearance to the body? Handling? Too bad, because it has partly been the issue of Q handlebar twist mentioned here in the forum which has made me wonder about how well it performs climbing, compared to the S or V. I'm surrounded by mountains.

Man, I wish I had a showroom of these bikes in front of me to compare things a bit better.

Ratz and Castleroober, re. the Q frame with 20 in. wheels: Oddly enough, I don't mind the look of the bike with fat 406 tires and drop bars, like Spin Cyclz built up once. Saw it on their Facebook page.

Thanks for helping me understand the issue, everyone.

 

[Bentas]

Mr Steve ,how did you attach those aero chain stays to the top tube ,the bb tube ?
And did the extended stays help performance apart from obvious aero advantage, ie climbing etc
Reason I'm asking is I'm in the process of building all carbon front end for this baby
Bike weighs 12 kilos now ,I'm confident with mods planned I can shed 3 kilos that's th e plan.

Cheers Rob

 

[ratz]

I've got a garage full of bikes and not one has external bearings. If I'm reading the problem correctly, it seems that the wider spindles being used by racers must increase the Q-factor (tread) of the bike? Seems counter-productive. I'll have to research that.

Harder to explain than it is to point at in person and show. Nothing to do with Q-factor.

Internal bearings mean thiner crank spindle which if hollow has more flex; if thick and stiff; then it's heavy. Move the bearings outside the BB and you can use a wider radius spindle which can be thinner metal thus lighter and still stiff. This is why the move from 24mm to 30mm has begun; because it's yet again lighter (thinner material) and stiffer (wide radius) which is good for racing.

As for the chain-stay clamps. The Q series used a pin-hinge narrow connection for the stay to the BB shell. That's heavy because of the welds and amount of metal needed; it's also flexy bendy under load because it's a narrow mount point. It's fine for it's intended purpose but not so much for the race frames. The race frame on the other hand clamp to the bearing cups. That's lighter with less metal and much wider keeping it stiffer; but the design limits the BB choices. So expect evolution on that front it's unavoidable. For this discussion it just address the lack of interchangeability

Now that I think about it, can't you take a Q bike and somehow just extend the boom toward the rider, just like a Silvio?

It's been done; it just limits the bike fit options and rider body dimensions.

rake and trail: I guess I've been imagining a new frame design with appropriate head tube angle, designed to accept a boom set up like the one on the Silvio.

The Q Series is using stock bike parts that you can google and see them in use on other bikes. The Silvio and Vendetta have custom designs; and unique wheel bases and handling characteristics. To make the stuff interchangeable the Q would need a custom front half and then the price point is shot because you are making low volume custom parts that require welding.

In the end you are "questing" for a solution that almost exists ; you just really need to get a Q series and see for yourself. There's not as much gap between you desires and the QX100 as you might think. Yes there's no exact prebuilt that you are looking for; it would likely sell for $1900-2200. Which is about what it would cost to get the existing stuff and enhance it. As always we are talking a niche need in niche sector, or a niche market. It's just not going to be market viable for them to solve the problem off the shelf at this time. So the only real choice is to customize.

If you fill out the test ride form on the front page Cruzbike will try to find someone Geographically near you so that you can go see the bike. That's pretty common; I have 4 people in the queue for this spring to come look at bikes..

If you do pursue a custom setup we'll all be really interested in what you settle on.

 

[1happyreader]

Who did this boom mod ??? anybody remember ?

 

[ratz]

Who did this boom mod ??? anybody remember ?

That's the one I was thinking of; I thought it was in the Q flex thread but it's not. It might have been from the tea leaves thread two years ago when the turbo quest was discussed. Hopefully the poster is still around and can chime in.

 

[MrSteve]

Mr Steve ,how did you attach those aero chain stays to the top tube ,the bb tube ?
And did the extended stays help performance apart from obvious aero advantage, ie climbing etc
Reason I'm asking is I'm in the process of building all carbon front end for this baby
Bike weighs 12 kilos now ,I'm confident with mods planned I can shed 3 kilos that's th e plan.

Cheers RobView attachment 2018

The attachment of the custom chain stay to the stock BB uses the stock BB mount (it was left alone) and the stock steel bolts
which connect the frame parts together. Reengineering this part of the custom chain stay was really tempting... because the steel bolts are
very heavy. But, it works fine and is extremely robust, so to save time I scrounged some copper water pipe that was a bit oversized (I.D.)
and cut everything to fit.
Taking up the slack between the stock steel bolts and the copper tube glued to the top of the chain stay, is some stainless steel
sheet shim stock. Put together with axle grease and torqued, the assembly moves freely enough, is stable under my power
and has shown very little wear over years of heavy use.

Also, to make this composite part as stiff as possible, it had to be much thicker and deeper overall than the stock
aluminum chain stay. Shaping it to shed drag helped to compensate for its size.

The advantage of this set up for me, aside from the obvious aerodynamic advantage, was to keep my hip angle
where I like to make my best power... for comfort!
See, with the low seat(s) I like, if I used those seats with the stock front end, my hip angle would be really open:
No good, for me.
So, yeah, it makes me a faster climber!

Please post a picture of your new front end?
When you're happy with it, of course.
I love your bike almost as much as you do!

 

[Emeljay]

1HappyReader: I saw the Vendetta/Sylvia like boom for the Quest in the Q Brag Board in thread Q Hybrid. I have been accumulating parts to do the same for my X100.