Thinking of buying an 857 but headset loose.

[leapinglizard]

Saw a Proflex 857 in a secondhand shop - got the guy down to $500 Australian ($US370).  Bikes in good condition - just needs some cabling adjusted but shocks etc are fine.  Just a stalling point though - I notice that the headset is loose at the top (where the bearings are located).  The play is only at the top and occurs in a forward direction when you apply the brakes (or lift the bike and move the handle bars in a forward direction).  I lifted the rubber seal at the top of the frame (between the headset and the frame) and could see the bearings inside which also moved in forward direction.

Can someone please give me some advice as to whether this is an indicator of the bearings or whether the problem is greater (and more expensive)?

By the way, everything on the front end (wheels etc) is original and straight.

Cheers

[northern_monkey]

hi
im no expert on proflex bikes but i know a little about engineering,  i would say that either the head bearings are not correctly adjusted maybe wrong spacers or they just havnt been set up correctly.or the bearing unit itself is shot, you will get more movement on the top bearing if its worn because thats where the leverage from the bars shows more.
if its was me i would also check for splits or cracks around the head tube, especially around the cups where the bearings sit. if someones hammered the headset in they could of goosed the tube.

[Tony Collier]

Thanks for that - I checked the head tube and the areas around the cups - all showed okay, no cracks etc.  I'm wondering whether the 857 has a locking nut at the top of the head tube as this is where the play is but it seems unusual that I can peel away the rubber seal to see the bearings - usually you have to undo a locking nut (between the headset and the head tube) to get access to the bearings?

Can anyone tell me if the 857 has a locking nut in this location (I'd be surprised if it didn't but better confirm with experienced Proflex users).

[kiwi]

i cant quite picture what you say is the rubber seal,but threadless headsets have no locking nut at the top of the headset,they rely on spacers and the clamping of the stem onto the steerer.If the shop is not proflex proficient AND the bike has the linkage fork they may have forgotten to loosen the ULM before attempting to adjust the headset.Say to them that you will buy it,but on the condition that 1) they fix the play in the headset,or 2) let you return it if you cant solve it(dont break it!) or if the problem returns after they do it.

[Matno]

Keep in mind that you could get a decent replacement headset for less than $20. As long as the cup itself isn't loose where it contacts the frame, that's not a big deal. If the cup IS loose in the frame, the frame is shot and you'll never have a tight headset. Don't ask me how I know...

Like Kiwi said, to access the bearings of a threadless headset (which an 857 undoubtedly has), you just remove the top cap and stem. Assuming you have a linkage fork, in order to tighten the headset properly, you have to loosen the ULM (the part of the upper linkage that attaches to the steerer) before tightening the top cap. Tighten the top cap until the fork has a tiny bit of resistance to being rotated side to side (with the handlebars), then back off the tension about 1/4 turn. At that point, make sure everything looks straight and tighten your stem clamp bolts to the proper torque. (If doing this by hand with a hex wrench, the proper torque is usually "really really tight"). Then you can retighten the ULM.

If you have a "normal" fork (i.e. not a CrossLink-type fork), ignore the parts about the ULM and do everything else in the same order. It's not very difficult. While you're at it, you might want to clean the bearings and add a little grease (not lube, grease) since you can already see them! Good luck.

If you don't want to tackle this yourself, take it to a real bike shop - they should be able to do it for a few dollars in about 5 minutes...