Any Tall Guys out there (like 6-4 plus) riding the Q45??

V

Victor Rader

New Member
Trying to figure out if I can fit on a stock Q45:

My X-Seam is 47.5 and my "leg length" to fit between the pedal and handlebar is about 26 so I need about 28 to allow a 2-inch clearance. Looks like the max stock distance is more like 25 inches. Pretty confident I could make the 47.5 by adding some new seat pan holes and even adding a longer crank, but a longer crank would decrease the 2nd clearance needed between the pedals and handle bars. Maybe CruzBike can make me a longer boom?

Anyone else been through this and figured it out? I really wanted to give this bike a try.

Thanks,
Victor
 
ratz

ratz

Wielder of the Rubber Mallet
Jim and Ken are both tall and fit on old-Q's and Vendetta just fine.

The boom length won't be the problem; the boom usually needs to be cut down. What you might need is a longer chain stay.
Now that the Q45 (I believe) has the same design as the S40 and V20 you probably could install the long chain stay.
@Robert Holler will know;

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Joe

Joe

Member
Cool pics, Ratz -- are the stories on these written up somewhere?

ratz said:
Jim and Ken are both tall and fit on old-Q's and Vendetta just fine.

The boom length won't be the problem; the boom usually needs to be cut down. What you might need is a longer chain stay.
Now that the Q45 (I believe) has the same design as the S40 and V20 you probably could install the long chain stay.
@Robert Holler will know;

View attachment 9239
View attachment 9240
Click to expand...
 
V

Victor Rader

New Member
From my research thus far and help from Robert at Cruzbike, it appears that the options are:
1) I might just fit with the seat all the way back (TBD)
2) Drill a net set of holes in the seat pan to move back another inch or so.
3) Add longer chain stays would raise the BB and add more leg extension
4) Adding longer crank arms (eg stock 175s) would add about .75inch more extension (and more torque that I don't need in Florida) but otherwise for a tall is short.
So I think some combination of the above will work.
Note: with the boom fully extended to the 24 mark (which is about an inch past the 20 mark as not all are marked the same way) there appears enough gap between the handlebars and the top of the leg. I need about 26+2= 28 inches and Robert measured 29 and that would leave about 2.75-jnch overlap between the slider and the boom which I think would be enough for a robust connection.
(to be continued)
 
Robert Holler

Robert Holler

Administrator
Staff member
PSA for everyone utilizing the scales on top of these booms and sliders:

Note that the relative position of these numbers is pretty pointless for a "universal" measurement as the etching on the tubes has moved over time and on different models.

As we have come to use the same boom and slider on the different bikes, they are finding a good place where they work for all the bikes, but your boom numbers may be different than someone else - both due to your physical fit/attributes, seat position, chain stay length, bike model, and when the boom was made since the scale may be an inch or more up/down the tube. The numbers you ultimately see line up on a Q45 are way different than on an S40 or V20 for example - even for the same rider, given all the other fit differences between the models.

The only substantial difference in tube lengths are the sliders for the FIRST run of Q45's - it is shorter than the rest. However we have spare "regular length" sliders for people who encounter those models and are tall (that run has long been sold out so would all be used-market Q45's at this point.)

Now, ALL sliders are the same length across all the models. The booms on the current generations of bikes have always been the same length even going back many production cycles.

For the next round of Q45's I am contemplating having a few "extra long" booms as spares made for taller fit - but that's a ways off so please - nobody hold any breath. :)

But in general a 2.75 to 3" overlap from a boom/slider tubes should be good I think.

Other fit factors that can improve room for very tall riders could also be changing to a different handlebar. This opens a much larger can of worms given there are a million bars on the market, but these are all standard parts.
 
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ratz

ratz

Wielder of the Rubber Mallet
Robert Holler said:
But in general a 2.75 to 3" overlap from a boom/slider tubes should be good I think.
Click to expand...

There is a thread in the history where IIRC Mark did the math; I think it was called "cut the boom" I'll find it tonight and cross post the info. If the thickness and metal type are the same we know do know the min that gives no loss. Use weight weenies were using that as the max cut off. I don't recall if he had the formula or just the answer. Worth digging up though just for fun either way.
 
Robert Holler

Robert Holler

Administrator
Staff member
Cool. I know Jim has made his lengths pretty custom on his race bikes to shave that small bit of weight. In general though I don't recommend any cutting except for short riders - and then only cutting enough to make the inward adjustment. Ideally the more tube overlap the better for overall stiffness.
 
ratz

ratz

Wielder of the Rubber Mallet
Ok that was a ride on the wayback machine to find the post.

The V20; boom from the Curved era metal, and thickness needs a minimum of 10 inches for full strength; I cut mine with 18inches of insert on the regular bikes which should accomdate at 6'5" rider. On my race bike I take it down to 10.5 inches.
 
V

Victor Rader

New Member
"a minimum of 10 inches for full strength" of overlap? If so that sounds like a test of how much overlap would be required to provide the same "break/bend" strength by exerting an equal force on both end at "some distance" away from the center, which I think is much more severe than the stresses that would occur while simply riding the bike? It seems like much of the stress would be in compression, by looking at the "triangle" and imagining the direction of the forces: there would certainly some twisting forces as well.

I went and picked up the bike yesterday and it seems I may fit with no additional mods at all. With the Seat Plate turned around and the seat slid all the way back and the boom at the "20" mark the leg extension was almost OK, but on the upstroke there was about zero gap, so extending the boom another 1.5 inch looks like that will work (for leg rotation with the 155 cranks) and about 3-inches of overlap on the tubes. The handlebar positioning felt fine. With the seat all the way back, the back of the seat was all the way to the support bar so it appears that would be max recline but the angles felt good. Unfortunately my knee is currently has some swelling and aching so further testing will have to wait: and hopefully in the next 2 weeks I'll be able to learn to ride and dial it in and can provide some pictures.
 
V

Victor Rader

New Member
OK I was too anxious to wait for full knee recovery and starting making adjustments. The bottom line is that with my 47.5 inch X-seam (that's barefooted) and 26 inch floor to "top of the leg" I can fit on the bike and I pulled myself forward and pedaled off down the street!! Yeah. I found out very quickly getting started and going straight is not bad; it's the steering! Wow, feel like someone turned off the power steering on a car. The good news is I was able to make a big wide turn in our cul-de-sac and the next step will be working on getting used to the steering, and I can see the brain will have to calibrate this into my subconscious so I don't have to think about it, and I'm sure it will given some time and practice.

So the adjustments I did make were to reverse the seat mount and slide the seat all the way, and extend to boom 1.5 inches past the arbitrary "20" mark which puts it about the "24" mark on some bars, leaving a 3-inch overlap between the 2 pipes. This leaves a gap of about zero on the upstroke but just touching and if I move my foot to the middle I have about 1/2 inch and a good inch if I move out to the ball of my foot, which I generally prefer but in the past have moved to the center to prevent foot pain. Some claim a middle position of the foot is better (for climbing) but that's another discussion somewhere I'm sure. This left the top of the boom (where the handlebars attach) 2 & 5/8 inch above the top of the upper ring, and feels fine. The middle point of the handle bars are about 10 inches from my body and I adjusted the handlebars just slightly forward of vertical (towards the front) to where it felt most comfortable for my wrist and the ability to pull back when pushing out with the legs. I never adjusted the height of the post (does anyone?) but I suppose that could also go up or down to put the handlebars in the most comfortable position. I moved the seat back position to hole #2 which is a little more upright and OK for now (in learning mode) and in the future for maximum recline it appears I could take out the "adjust" bracket altogether but then I would lose the upper tie points for the rack. In hole #1, it would flip over like a clamp if that makes sense and rest against the seat which is probably fine but I think I would rather block that up with a spacer.

Note: if I was back in the great Pacific Northwest, land of hills, I would want a much longer crank arm (which makes you instantly way more powerful (which is also another discussion)) but in that case I may need to go to longer chain stays which I think alone would increase the leg extension and possibly a longer "slider". My primary intrigue all these years has been the connection to the upper body for hill climbing and here I am in Florida where the only hills I've seen are called bridges.

This should be a new thread also, but just wondering beyond that connection to your core and upper body are there other reasons you'd prefer this design over a traditional recumbent?

Thanks in advance for any further suggestions, and once I get some pictures on my computer I suppose I can "upload a file" and show some photos.
 
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