Q559 Quick Front End Stiffener…

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Postapocalypsia

Active Member
Hi Folks,
Just tried a quick mod on the front end to make better triangulation and diminish the potential flex in the riser tube.
I bought a 2nd riser tube clamp from cruzbike hq, and fitted it at the top of the riser with help from a homemade shim. Now the boom slider attaches at the top instead of the bottom. I have seat moved back which helps to keep the boom shorter and less prone to flexing.
I don’t have any way to measure the difference but it feels like I have more torque steer, which suggests less flex…could be my imagination but I am happy with the change.
Has anyone else with an older Q tried this?
45225E51-EF9E-4B58-90CA-D9295433E115.jpeg
 
Rampa

Rampa

Guru
See if you can find a way to move your seat back a few more inches. Then you can shorten up the slider tube. You can also raise your cranks higher if you can manage that.

But an Emeljay mod may be more useful still!
 
P

Postapocalypsia

Active Member
billyk said:
Yes, considerable discussing on these points. Your mod should indeed help.

See some earlier posts:
Quest frame flex tested" (http://cruzbike.com/forum/threads/quest-frame-flex-tested.7794/)

Also look for posts about the "emeljay mod" for a more radical (but doable) approach:
"Qx100 steering mod".
Click to expand...
Hi billyk - had a good read of the flex-test thread with interest …admittedly I have no engineering clout to contribute, but found some useful info, thanks.
I suspected the riser tube was complicit to the flex, so I lowered my top clamp and bar clamp as much as possible without hitting my legs on the handlebar. Luckily my bars have plenty of forgiveness (Soma Sparrow).
Next trick is to shorten the slider tube - it’s a WIP!
Thanks for your insights
 
P

Postapocalypsia

Active Member
Rampa said:
See if you can find a way to move your seat back a few more inches. Then you can shorten up the slider tube. You can also raise your cranks higher if you can manage that.

But an Emeljay mod may be more useful still!
Click to expand...
Hi Rampa - my seat is already set back but I note the point you are making…the further back the pedals, the shorter the slider, the less length to flex - the added bonus would be straighter arms and more cockpit room!
The Emeljay mod looks like winner but I suspect the Diatech headset on my Q would not allow the same boom connection as the Qx100.
Thanks!
 
Bikes&Banjos

Bikes&Banjos

Member
Just seeing this for the first time. I bought a used Q559 last month and have been learning to ride it and experimenting with fit and other customizations. As a relatively large guy, I'm feeling a lot of flex in the extended riser tube and stem extension that I've set up. Especially when climbing my neighborhood hills.

This fairly simple mod looks like it would help stiffen my front end flex issues a little. After a couple of weeks with this update, are you still feeling pretty good about it?
 
billyk

billyk

Guru
Postapocalypsia said:
I bought a 2nd riser tube clamp from cruzbike hq, and fitted it at the top of the riser with help from a homemade shim.
Click to expand...

Interesting idea.

These bikes take a lot of bending forces between the bars and the pedals. My observation has been that flex comes from every long tube and every joint. By bringing the boom up to the bars you've reduced one limb of that.

But there's that shim joint. A definite source of flex. Can it be as rigid a connection as a clamp directly on the head tube? I'd say, pay attention to that and think about making it as tight as possible.
 
Bikes&Banjos

Bikes&Banjos

Member
Just to follow up on this. I asked Robert from Cruzbike how much it would cost for an extra riser tube clamp and he says they don't have any spare parts for the Quest 3.0 any more.
 
Rampa

Rampa

Guru
Check out "scooter clamps" as a possible alternative. They come in 1 1/4", and multi-bolt options.
 
P

Postapocalypsia

Active Member
Bikes&Banjos said:
Just seeing this for the first time. I bought a used Q559 last month and have been learning to ride it and experimenting with fit and other customizations. As a relatively large guy, I'm feeling a lot of flex in the extended riser tube and stem extension that I've set up. Especially when climbing my neighborhood hills.

This fairly simple mod looks like it would help stiffen my front end flex issues a little. After a couple of weeks with this update, are you still feeling pretty good about it?
Click to expand...
Hi, sorry for the slow response…short answer, yes, I am feeling pretty good about it.
Like other respondents have noted, the quest has a number of points at which the flex can creep in. I can see I will never eliminate it altogether but this relatively simple mod has made a difference. I have considered trying something similar to the emeljay mod but haven’t got around to it yet. I did find an aluminium tube size that would sleeve over the lower section of the boom which would theoretically be stronger, but then I would be playing catch-up trying to reconcile the fit at the riser/handlebars.
Nowadays I spend more riding time on my S40 which has a bombproof boom so I can compare the difference.
The other change I made earlier on the quest was to swap out the riser tube clamp bolts for a higher tensile version which meant I could confidently tighten the diatech headset consistently without fear of breaking the bolts. This helped take any play out of headset.
The quest is my favourite for rough ground and just larking around, I just accept that it takes a bit more grunt to get up the hills.
BTW are you a banjo player?
 
Bikes&Banjos

Bikes&Banjos

Member
Postapocalypsia said:
Hi, sorry for the slow response…short answer, yes, I am feeling pretty good about it.
Like other respondents have noted, the quest has a number of points at which the flex can creep in. I can see I will never eliminate it altogether but this relatively simple mod has made a difference. I have considered trying something similar to the emeljay mod but haven’t got around to it yet. I did find an aluminium tube size that would sleeve over the lower section of the boom which would theoretically be stronger, but then I would be playing catch-up trying to reconcile the fit at the riser/handlebars.
Nowadays I spend more riding time on my S40 which has a bombproof boom so I can compare the difference.
The other change I made earlier on the quest was to swap out the riser tube clamp bolts for a higher tensile version which meant I could confidently tighten the diatech headset consistently without fear of breaking the bolts. This helped take any play out of headset.
The quest is my favourite for rough ground and just larking around, I just accept that it takes a bit more grunt to get up the hills.
BTW are you a banjo player?
Click to expand...

Good to hear you're still feeling pretty good about it. I think I'm probably going to get my hands on one of the scooter clamps mentioned above and make this mod on my Q.

And yes I'm definitely a banjo player. I play in a couple bands around Baltimore
 
Rampa

Rampa

Guru
Postapocalypsia said:
Hi, sorry for the slow response…short answer, yes, I am feeling pretty good about it.
Like other respondents have noted, the quest has a number of points at which the flex can creep in. I can see I will never eliminate it altogether but this relatively simple mod has made a difference. I have considered trying something similar to the emeljay mod but haven’t got around to it yet. I did find an aluminium tube size that would sleeve over the lower section of the boom which would theoretically be stronger, but then I would be playing catch-up trying to reconcile the fit at the riser/handlebars.
Nowadays I spend more riding time on my S40 which has a bombproof boom so I can compare the difference.
The other change I made earlier on the quest was to swap out the riser tube clamp bolts for a higher tensile version which meant I could confidently tighten the diatech headset consistently without fear of breaking the bolts. This helped take any play out of headset.
The quest is my favourite for rough ground and just larking around, I just accept that it takes a bit more grunt to get up the hills.
BTW are you a banjo player?
Click to expand...
I used a fatter tube on my Emeljay. It means you need to cut a squeeze groove to clamp it to the inner tube. I had to go with a bit thinner wall than I really wanted, otherwise the OD would have been to far over 1.5 inches to work. There are 1.5" stems available, and my OD ended up at 1.51". It is snug, but works well. I think the inner tube Emeljay variant is easier, and can be a little thicker wall tube to make up the difference in strength.
 
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