ISO ss or ss-compatible 175 mm lowish-Q square taper crank for 32 t single ring

[Patrick Moore]

Riding the Monocog again today I once again thought that it would be nice to remove at least 10 mm from the present 168 mm Q of the Truvativ crank which has 15 mm right and 22.5 mm left clearance; I need 5 mm per side at most, so could theoretically reduce Q to just over 140 mm on this frame, tho' I'd be happy to reduce it below 160 mm. 168 mm q is rideable, but trying to spin the 65" gear fast with the longer 175 mm arms emphasizes the width.

At any rate, would like to find a small bcd crank with less flare for which 32 t rings are not too hard to find -- 32 happens to work well with a 15 or 16 t cog and my wheels in this frame. I am only familiar with 110, 130, and 144 bcds, so I'll need instruction on what to avoid as well as what to seek. I think my Truvativ has a 104 mm bcd as the distance between adjacent bolts is about 73 mm. 104 mm bcd cranks and rings seem to be popular BMX components, no? They are cheap. What are good makes and models, with a premium on (in descending order of importance) Q, quality, price, color (black first, silver second, could use red)?

For used, not interested in very high dollar -- can move to 110 bcd if need be with larger ring and cog; but interested to hear what you have to offer.

Also interested in 2-piece cranksets if 32 t ring and low Q as described, and tolerably durable bearing system for very dusty and gritty surfaces.

Thanks.

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Patrick Moore

Alburquerque, Nuevo Mexico, Etats Unis d'Amerique, Orbis Terrarum

[Patrick Moore]

[masmojo]

I'm afraid BMX and offroad folks in general don't really think about Q-factor and would likely look at you funny if you talked about it much.

That said; it sounds as though a simple BB swap would solve 80-90% of your problem?

10mm shorter spindle should be doable based on the measurements you've given above.

 I can however recommend a couple Square taper BMX cranks that you can generally find on ebay for between 55 & 100 dollars without too much effort.

I have some Promax SQ-1's on my Bombora and I am  pretty happy with them, they come in a variety of colors and Lengths and are generally less than $60.

Also for about $70. you can get the BOX Five Square tapers, better know name, but not as much variety.

I don't know the Q on either of these, but judging by the Promax on my Bombora they are not low Q!!!

Great thing is they are cheap, so you could get some, mount them and if they are too wide, get a narrower BB spindle.

actually you could probably do both, New crank and new 10mm narrower BB.

Just search Cold forged Cranks on Ebay.

Good luck

[Eric Daume]

BITD, I achieved a ~155mm Q factor on my Karate Monkey (73mm bb) with a Suntour XC Pro crank. Very thin arms on that model. 94BCD x 5 bolt is made for 32t rings. 

Eric

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[Patrick Moore]

Thanks all for the info and tips. Brian, thanks for the offer. I think Bill has found a solution. I will report on eventual Q.

The new cranks may be a silk dress on a pig, but I do have hopes to replace the frame before too long with one with more rear tire clearance, and would be getting new cranks for that anyway. So, hurrah. Next project, getting some inline Travel Agents and reverse brake levers to free up an unobstructed curve of handlebar real estate for taping and more comfort; the present brake lever clamps interfere with the transition between Ergon grips and taped curves.

[Patrick Moore]

https://www.modernbike.com/sram-bl990-aero-brake-lever-set-with-cable-adjuster

Interesting, fwiw: adjustable cable pull. But not at that price, and the shape of the lever is wrong.