Showing posts with label digital gauges. Show all posts
Showing posts with label digital gauges. Show all posts

Wednesday 8 June 2022

Bum Steer AKA Its Too Tight, Or Its Too Slack..










 I had a model cancel a shoot, which is annoying but comes with the territory. This presented an ideal opportunity to investigate some issues with my fixed gear winter/trainer’s recently replaced Aheadset.  

I’d pensioned off the long serving FSA, which had served faithfully for five fairly hard years. The lower race employed a cartridge bearing, the upper traditional balls, which keeps costs down, but I fancied something a little more refined, hence the Stronglight.  


However, despite having everything correctly aligned, it wouldn’t adjust properly. Removing slop meant tightening bearings to the point the bars would barely turn. Something was clearly very wrong, and I wondered if this was indicative of a more serious fork steerer issue.   


A full strip and diagnostic session followed. I dismissed the Gusset Uni-Lock Headlock, inspected the fork steerer, paying particular attention to the crown area and went the SFN (Star Fangled Nut) route.  


I then dismantled the headset and found while new, it was a “Franksenset”. One cobbled together from two superficially identical but ultimately, incompatible models (which in retrospect, explains the issues and why it was so cheap). The compression ring being a case in point. Given it was boxed and sealed, I had no reason to think anything was "off".  


Decision made. No sense attempting silk purse from sow’s ear. Might as well start again...The cartridge bearings would be useful but otherwise, I put it down to experience. Thankfully, I found a complete, sealed Olite I’d bought a while back. This also proved an ideal opportunity to use a tube of Park PPL grease that was splitting along the seams.  


Lashings of the tenacious green goo delivered to the cups and races-buttery smooth. New stem bolts, (since the Redshift Sports Shockstop Suspension Stem TEST & REVIEW REDSHIFT SPORTS SHOCKSTOP SUSPENSION STEM (sevendaycyclist.com)’s  were getting a little chewed) some fresh thread lock on the disc caliper mount hardware, some spacer-switching... 


Time consuming but formative checks confirmed things were broadly right, so I fine-tuned the preload and snugged the stem bolts to 5nms. Cane Creek SC5 CANE CREEK V BRAKE DROP BAR LEVERS | cycling-not-racing (sevendaycyclist.com)lever engaged and several, neurotic rockings later, I couldn’t trace any slop, so tethered the K-Lite dynamo K LITE BIKEPACKER ULTRA DYNAMO LIGHT | cycling-not-racing (sevendaycyclist.com) cable to the Kinesis fork leg.  


Of course, I wasn't done there!  


Tyres inflated; pedals switched in favour of the Shimano XT, chain tension tweaked and finally, Motoverde PTFE Chain LubeMotoverde PTFE Chain Lube | cycling-not-racing (sevendaycyclist.com) stripped in favour of this Momum Mic Dry Lube. I finished by giving the frameset a light waxing, buffing with a micro fibre cloth, then popped it away.  


There’s a fine line between staying with something until you’ve got it sussed (and sorted) and quitting while ahead.  Sure enough, the following morning’s shakedown ride confirmed the bearings were a little too snug.  

 

Slackening the stem bolts, I loosened the pre-load by 16th turn, did the rocking back and forth test, then tightened the stem bolts to 5nms.  Cue loud (internal) cheer-it was 5.50am and I didn’t think my neighbours would be so appreciative, dare I say empathetic.  When it comes to bearings, headset and bottom brackets, I preside durability and weather sealing above weight and indeed price. Needle bearing models that displace loads were particular favourites 


The Teenage Dream was originally built, (back in ‘91) with a Primax unit featuring these, which might seem strange given needle roller bearing models were a tourists’ choice and said machine was a sunny days, pared to the essential's plaything...I’ve run them up to very high mileages on traditional touring lorries but they’re also a good bet for bikes that regularly lug trailers and indeed, tag-alongs.  


Decent waterproof greases, including the Park, or White Lightning Crystal TESTED : WHITE LIGHTNING CRYSTAL GREASE (sevendaycyclist.com) certainly help extend service intervals, without shortening component life. Mudguards (Fenders) also make a big difference but if this isn’t an option for you, make a boot from old inner tube to protect the lower race.  


Obviously, being butyl go for a synthetic grease, rather than the old school lithium, or PTFE infused blends, since these will rot rubber-another consideration if headsets employ rubber seals.  Green Oil Eco Grease TWELVE MONTH TEST: GREEN OIL ECO GREASE (sevendaycyclist.com) is a surprisingly stoical alternative, albeit not rivalling the Park, or White Lightning blends discussed.