What bb to go with Lasco "track" cranks?
 

These Lasco cranks I bought are said to be JIS taper but even on the shortest JIS spindle I could find (103mm) they sit too far out away from the frame. So I am thinking of going with an ISO taper instead - AKA Campagnolo/italian square taper.

The question is should I get a 103mm wide ISO spindle or will that be too short to the point where the cranks bottom out? I'm trying to get that tucked look against the bb shell.
Has anyone got previous experience with Lasco "track" cranks? I hear that they are machined quite poorly - I wish I knew this when I originally bought them :( - hence why they are sitting too far away from where they would ideally be, both for a shorter q-factor and for aesthetic purposes.

The Lasco single chainring (track) cranks that came on my two bikesdirect bikes use a 103mm JIS spindle and the chainline seems fine to me. How is the chainline on your bike, because that is the determining factor as to the correct spindle length ? You don't choose spindle length based on aesthetics or q-factor.

I would be careful with installing a JIS crankset on a ISO tapered BB. You increase the risk of bottoming/rounding out the crankset taper that it could render it useless, especially for cheaper cranksets with lower tolerances and QA.

@Zdawg - I exchanged a few posts on this exact same...errr...subject with a guy in a SS/FG group on FB a few weeks ago. I'm not in the mood search it out and my memory ain't so great anymore so you gotta help me - was that you? If it was - please, please, please get yourself to 10 posts so you can post those same pics here so the group can see what you are going on about. And if you could point me to that discussion it would be great.

Yes, BFSSFG sub-forum that (& maybe this) guy was so concerned about getting his crankarms tukt way into the BB that he had already deformed the tapers on a set to the point of bottoming out, and liked it, and was looking to do the same on another set via bouncing between ISO and JIS tapers and different axle lengths to get that Sw8 Tukt BB/crankarm interface.

So have you learned anything interesting on this...errr...subject since last time we talked about it? ✌️

IAmSam Yeah, I've posted the same question on a couple of facebook fixed gear pages. Here are the pictures of the Lasco cranks on a 103mm JIS spindle and after that a picture of Sugino RD2s also on a 103mm JIS spindle. You can notice the difference between the degree of "tucked-in-ness", the RD2s sit perfectly flush without bottoming out. Now, my plan is to buy an ISO spindle bb because I know it will allow the Lasco cranks to sit closer to the shell and give that nice, tucked look. The problem is I don't know which length ISO to go with. There is a 103mm ISO selling online, I might start with that one, and if that doesn't work go with the next length up. Hopefully it doesn't get too expensive.
https://cimg1.ibsrv.net/gimg/bikefor...dcfeb561ca.jpg
https://cimg0.ibsrv.net/gimg/bikefor...0342f27927.jpg

I am so glad to learn that I was not imagining it :D

Thanks for the pics - now that is...Tukt. As ridiculous as I think this is - it is your bike and I hope it works out for you.

Guess it will be up to the forum to reply further if they are interested.

Good luck...

The Lasco and Sugino RD2 cranks are completely different, such that the Suginos need to fit closer to the frame for the chainring to sit in the correct line with the freewheel or cog. If you move the Lascos closer then your chainline will be off and the chainring or crankarms may even contact the chainstays. Like I said in my first post, the choice of BB spindle length should be based on chainline and not on aesthetics or q-factor. I have a feeling that my advice will fall on deaf ears, since you seem to not want to listen to reason.

@TejanoTrackie Yes, yes, yes. I'm taking all of those into consideration when putting the new system together. Would you tone down the smugness if I said the chainline is also too far away from the frame?

I've seen your replies on other threads here and there, always with that prideful attitude. For goodness' sake, guy literally refers to himself as 'Reason' incarnate. Let's take it down a notch, bud.

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Hey dude, it's your life and your bike. Eff it up if you want to, I really don't give a rat's ass.

Oh give me clarity, track lord
 

How am I effing up my bike??? What do you think is going to happen, I'm going to keep cycling if there's any rub or strike of any components?

Please explain why you think what I'm going is so objectionable

You should get off your high horse, mate. Your builds aren't that nice to justify this level of smugness. You sound more like a roadie who kept getting dropped in the group rides, adopted a new identity as a "trackie" and now spends his time belittling other genuine fixed gear riders in forums

Hey guys. Let’s take it easy. Advice was given and received. Let’s move on now.