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Technical & Reference Section => Tech and Restoration => Topic started by: chi11i on May 03, 2009, 08:41 AM
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Hi - not sure if tech question about NS goes here or in NS bit - try here first.
Have a new NS (Fit Trail 3 from rad shop) love it. Front wheel has slightly loose bearings - the play isnt at the axle so i dont think tightening the two bolts (a bit like old cone nuts) makes no diff, it seems to be slight lateral play between bearing and hub shell. i can live with it, but is it normal? ive been running sealed bearings on the front of mtb dirt jumpers and 4X bikes for years and not had any issues.
what do i tighten? or do i ignore it?
ta, S
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pretty sure well very sure the sealeed bearings run same as the unsealed ie the bearing cones ned tightening little bit .i have seale old school suzue hubs and they are same cones to tighten onto the sealed bearing and i had to adjust em up bit
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The bearing should be a press fit in the hub - there should be no movement.
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What Twobob said, almost certainly a manufacturing fault. (overmachined Hub)
Jedi had the same problem with a Fit BB shell think he got the frame replaced under warranty.
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If you dont go down the warranty route you could use bearing lock a liquid similar to thread lock which would secure the bearing in the hub, its not the most professional repair but would be better than binning the wheel. (Loctite make it)
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I may be wrong but I doubt that they are sealed bearing hubs , You will find they are normal open bearing cones and locknut with a rubber seal covering them up . In other words you need to tighten up your cones , job done. :daumenhoch:
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Thanks all. Def sealed, def press fit. Just had it apart. The two lock nuts were tight on each side and there's still about half a mm play - which aint a lot i know until you start banging the front around on the ground - perhaps my learning 180 hops hasn't helped ;)
Oddly, after putting it together again - i couldnt feel the play when lofting and dropping the front when riding, but i can feel it by hand! anyhow, will see how it goes. im used to building my own wheels for mtb/dirt and im quite critical of machine made ones generally (the front wheel is also not dished proper either) but never had press fit bearing wobbling before.
One last question - do people actually fit those 'safety' drop out washers (dont know what they a properly called) that hook over the slot in the drop out? the ones supplied with the fit are huge and dead ugly, so i left them off - just wondered - im not that paranoid about the front wheel dropping out. i see they are not on the pics on fits website - but then neither is the next to useless 'legal' front caliper.
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I'm slightly confused now... where is the play? at the axle/bearing or at the bearing/hub?
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yep sounds like over machining it cant rearly be fixed replacement needed.
if it was axle to bearing id od then still it would need to be a good good almost airtight gap minimum.
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bearing/hub is where the play is - not axle. sorry my rambling there was a bit unclear wasn't it. its lateral play not radial so as you suggested hub shell prob machined out a gnats too deep.
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have you tried to shim it out.
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no - would need super thin shims. would you suggest trying 'behind' bearing? as in pop bearing out, insert shim, replace bearing?
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its easy for me as i dabble in fiddly things like this but behind the bearing would be better keeps the face flush
i run king axles and they float no problems with them
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ta - how do you mean 'float' - as in the hub shell/bearing interface has some intended play?
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Those hooked washers are a good idea in my opinion.I heard a lad at creation had his front wheel come off and he has broken his back.Maybe someone fookin' around with spanners...
I had a bit of play in my front hub after about 4 months riding.Took it apart and gently tapped the bearings back against the hub seating,put it together and put new thin shim washers between the hub nuts (they are what wear and cause the symptoms).Nipped up the nuts and job done.
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Cherers Voodoocars - think I'll prob leave it for a few more days and see how it goes. thinking about it last night not sure how a machined hub could go that wrong from a super mass produced taiwainese factory all controlled by computer - or maybe not!
Agree with washers - might have a look for some smaller ones - i guess the ones supplied were big fattuns to work with a peg? which i'll not be running ever i dont think.
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I dont think anyone tends to run those safety washers but I agree there a good idea for kids who have no bike maintenance skills, it does not surprise me to hear of riders losing front wheels etc.
I witnessed a kid at Unit23 who was fitting his front wheel with only an adjustable wrench, he was running a peg so could only tighten the non peg side. when I offered him a loan of my tools he said "nah its alright I will just tighten this side real tight" he then proceeded to do flips whips etc and you could hear his front axle smashing against the dropouts he then asked me to tighten the loose side.
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Thought they were a bit H&S. I have had issues with an mtb front wheel where the qr had come loose (and i'm good at checking them a lot - ended up being a fault on the qr) and had to bail on the dual slalom at chicksands - not pretty. now ONLY use bolted hubs on mtbs that get regular abuse.
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Thought they were a bit H&S. I have had issues with an mtb front wheel where the qr had come loose (and i'm good at checking them a lot - ended up being a fault on the qr) and had to bail on the dual slalom at chicksands - not pretty. now ONLY use bolted hubs on mtbs that get regular abuse.
Yeah I'm not really a fan of MTB technology but the 20mm front through axle is deffo a good idea, QR axles are horrible.
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yep i hate the QR axles they just dont seem a good idea .
axles should and all could be push throu a hole in the fork rather than slot.
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Whats a QR? Pleas excuse my ignorance as I know very little about modern mtb technology
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quick release you turn the arm to nip up the wheel.seconds in and out.
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Oh yeah doh :crazy2:
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yep - 4X bike has Pikes on the front with a 20mm push through axle - strong as hell. dirt jump bike has 10mm bolted front. to be honest, now im back on 20" wheels - think they might be on ebay at the end of summer if i dont ride them - def the dirt jumper. its a sweet build (dialled bikes prototype frame) but 20" feels so natural - now anything else over jumps feels lanky.