adg44 Posted May 6, 2015 Share Posted May 6, 2015 I've noticed this for a while, but whenever I'm braking, regardless if it is from 70 MPH or 40 MPH, once the speed passes through 30 MPH, I get a wobble through the bars. It does this if it is a hard brake or a light brake. Any ideas? I just passed 12,000 miles on the bike. Took it out for the first ride of the season and it fired right up and ran perfectly after sitting hooked up to a trickle charger for the past 6 months. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
Member Contributer Cogswell Posted May 7, 2015 Member Contributer Share Posted May 7, 2015 If it's only during braking, check the runout of the rotors. If it also does it when decelerating without using front brakes, check for cupped or scalloped tires (and correct pressure), loose steering head bearings, bad front wheel bearings or sticking or loose calipers. Link to comment Share on other sites More sharing options...
number9 Posted May 7, 2015 Share Posted May 7, 2015 If it's only during braking, check the runout of the rotors. If it also does it when decelerating without using front brakes, check for cupped or scalloped tires (and correct pressure), loose steering head bearings, bad front wheel bearings or sticking or loose calipers. For those of us without dial indicators, what's an easy way to check run-out? Link to comment Share on other sites More sharing options...
Member Contributer gig Posted May 7, 2015 Member Contributer Share Posted May 7, 2015 You can get a dial indicator from harbor freight for $32.00. I had the same issue, and was able to straighten my rotor/carrier with info from a thread. Your Store: Asheville, NC Store Info (change) FIND STORE SALE & CLEARANCE MONTHLY AD SHOP BY INTEREST INSIDE TRACK CLUB HFT GIVES BACK POWERTOOLS AIRTOOLS HANDTOOLS TOOLSTORAGE AUTOMOTIVE& MOTORCYCLE ENGINES & GENERATORS WELDING LAWN & GARDEN MATERIALHANDLING EVERYTHINGELSE Home | Clamping Dial Indicator Double click on above image to view full picture Clamping Dial Indicator Pittsburgh - Item#93051 Read 17 Reviews Write A Review This clamping dial indicator mounts almost anywhere Only: $34.99 Sale: $32.99 Qty: Add to Wishlist View Shipping Rates Link to comment Share on other sites More sharing options...
TNRabbit Posted May 7, 2015 Share Posted May 7, 2015 There's a thread here about lubing & rotating disc buttons. I did this & it completely stopped a similar vibration I had on my 98. Link to comment Share on other sites More sharing options...
Member Contributer zupatun Posted May 7, 2015 Member Contributer Share Posted May 7, 2015 IMO the most likely common cause is worn stock/factory steering head bearings...with used tires. Going to taperd roller bearings reduces this significantly..multiple threads and postings on the subject. I have also gone through and trued my brake rotors...every little bit helps. Matt Link to comment Share on other sites More sharing options...
Member Contributer Dutchy Posted May 7, 2015 Member Contributer Share Posted May 7, 2015 <p> You can get a dial indicator from harbor freight for $32.00. I had the same issue, and was able to straighten my rotor/carrier with info from a thread. That is a nice tool! Must speak with my Trans Atlantic mule :-) Link to comment Share on other sites More sharing options...
marriedman Posted May 7, 2015 Share Posted May 7, 2015 I'll second the head bearings. I had the same symptom but at around 40mph. Tapered bearings from All Balls not only fixed it, but also made it better than stock IMO. Link to comment Share on other sites More sharing options...
number9 Posted May 7, 2015 Share Posted May 7, 2015 <p> You can get a dial indicator from harbor freight for $32.00. I had the same issue, and was able to straighten my rotor/carrier with info from a thread. That is a nice tool!Must speak with my Trans Atlantic mule :-) I can pick you up & mail you one if you need it. Link to comment Share on other sites More sharing options...
Member Contributer VFROZ Posted May 8, 2015 Member Contributer Share Posted May 8, 2015 Don't bother with disk tools. It will be your steering head bearings. A warped disk will pulsate or vibrate, it won't wobble your bars. Worn/lose bearings will. Link to comment Share on other sites More sharing options...
Member Contributer Dutchy Posted May 8, 2015 Member Contributer Share Posted May 8, 2015 <p> You can get a dial indicator from harbor freight for $32.00. I had the same issue, and was able to straighten my rotor/carrier with info from a thread. That is a nice tool!Must speak with my Trans Atlantic mule :-) I can pick you up & mail you one if you need it. Cheers! But shipping and Dutch Customs will have $$$ field day...... Muling it will have to be.... Link to comment Share on other sites More sharing options...
number9 Posted May 8, 2015 Share Posted May 8, 2015 You would have to pay customs on something so cheap? Link to comment Share on other sites More sharing options...
Beck Posted May 8, 2015 Share Posted May 8, 2015 Check everything as noted, but the quickest easiest check woudl be the condiion of your tires. tread cupping on the front tire will, in most cases, cause such wobbles during braking/decelerating. Change the front tire if it is cupped. Doing such solved my own similar wobble problems when I changed my Dunlop "cupmonster" tires to much better Michelin PR's...... Link to comment Share on other sites More sharing options...
Member Contributer BusyLittleShop Posted May 8, 2015 Member Contributer Share Posted May 8, 2015 You have experienced a deceleration shimmy and it's normal...some bikes may shimmy decelerating through the 45 mph range... keepingyour hands on the bars should arrest most of the front end shimmy...some bikes shimmy more than others and it's no big deal with yourhands on the bars in the critical speed range... your bike should beimmune at speeds above 45 mph...Deceleration shimmy is chiefly the product of non OEM or a worntires... it ain't the product of tire cupping... but low pressure orloose steering head bearings defeat the tire's corrective efforts...because every bike has this instability... it is held in check bydamping forces created mainly by the tire's self-correctingtendencies... In short...Deceleration Shimmy = front tire problems... (annoying)...Wobble = front end problems... (could grow into the dreaded tank slapper)Weave = rear end problems... (annoying)... STEERING HEAD BEARINGSIf your steering head bearings are too tight the bike will wonder andnot seek it own center... if you're steering head bearings are looseyou'll notice a pronounce clunk during braking... I don't use torquefigures rather I raise the front wheel off the ground and tighten thesteering head bearings until the bars lock then I back off the nutuntil the bars free wheel with a slight drag... with this method youfind that sweat spot and avoid over tightening and under tighteningeven if you upgrade to taper roller bearings... Link to comment Share on other sites More sharing options...
number9 Posted May 9, 2015 Share Posted May 9, 2015 Don't bother with disk tools. It will be your steering head bearings. A warped disk will pulsate or vibrate, it won't wobble your bars. Worn/lose bearings will. Mate, how does one definitively test for bad steering head bearings? Thanks! Link to comment Share on other sites More sharing options...
TNRabbit Posted May 9, 2015 Share Posted May 9, 2015 To check steering head bearings: 1- put bike up on center stand 2- have someone sit on the back of the bike so the front is raised off the ground 3- move the steering wheel from side to side feeling for any notchiness or uneven movemment 4- if they're worn it will probably be a center notch where it will recenter itself Link to comment Share on other sites More sharing options...
adg44 Posted May 9, 2015 Author Share Posted May 9, 2015 Good info here, guys. I am quite positive it's not the rotors, as there is no pulsation or vibration in the brake lever, and this only happens at ~30MPH, whereas the rotors should do it whenever the brakes are applied, and especially at higher speeds. Does anyone have a how-to on changing the steering head bearings? Link to comment Share on other sites More sharing options...
Member Contributer adeyren Posted May 9, 2015 Member Contributer Share Posted May 9, 2015 Not too bad a job, easier than i thought, never done them before. Just follow the manual for removal. Hardest part was driving the new bearing races home. As i am a tightwad and didn't want to buy all the pullers etc etc i made this up from some allthread, various sockets and knackered Citroen suspension bushes! Dont all laugh but it worked a treat. Ps flask was just sat there NOT part of the tool. Link to comment Share on other sites More sharing options...
TNRabbit Posted May 9, 2015 Share Posted May 9, 2015 Good info here, guys. I am quite positive it's not the rotors, as there is no pulsation or vibration in the brake lever, and this only happens at ~30MPH, whereas the rotors should do it whenever the brakes are applied, and especially at higher speeds. Does anyone have a how-to on changing the steering head bearings? Don't be so positive. I had a similar vibration only at around 30 miles per hour and it ended up being the bobbins on the discs needed lubing. Link to comment Share on other sites More sharing options...
Member Contributer Dutchy Posted May 10, 2015 Member Contributer Share Posted May 10, 2015 Freeing/lubing the bobbins.... I saw a video on that a while ago and to be sure phone EBC Brakes' tech department in the UK. They had never heard of that, didnot feel it was required and IF I wanted to do that procedure with the bolts and washer I was told to be very careful with the applied pressure... I will clean mine with brake cleaner today and see if I can ascertain any difference though... Link to comment Share on other sites More sharing options...
TNRabbit Posted May 10, 2015 Share Posted May 10, 2015 Well, it worked great for me. Also, no more than finger tight on the bolts is all that's necessary. Link to comment Share on other sites More sharing options...
Member Contributer gig Posted May 10, 2015 Member Contributer Share Posted May 10, 2015 Freeing/lubing the bobbins.... I saw a video on that a while ago and to be sure phone EBC Brakes' tech department in the UK. They had never heard of that, didnot feel it was required and IF I wanted to do that procedure with the bolts and washer I was told to be very careful with the applied pressure... I will clean mine with brake cleaner today and see if I can ascertain any difference though... i used rubber washers against the buttons to grip them without having to apply much pressure. The cleaning did eliminate the low speed brake pulsing i had. Bolt - washer- rubber washer - "button" - rubber washer - washer - nut Link to comment Share on other sites More sharing options...
adg44 Posted May 24, 2015 Author Share Posted May 24, 2015 Freeing/lubing the bobbins.... I saw a video on that a while ago and to be sure phone EBC Brakes' tech department in the UK. They had never heard of that, didnot feel it was required and IF I wanted to do that procedure with the bolts and washer I was told to be very careful with the applied pressure... I will clean mine with brake cleaner today and see if I can ascertain any difference though... So did it work for you? Link to comment Share on other sites More sharing options...
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