fork mod

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canappa
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fork mod

Post by canappa »

well im completely rebuilt my 92 fzr forks (new racetech springs 0.90kg/mm, gold valve, racetech bushing, etc), I want to do a little mod to the outer tube to allow it slide throw the upper triple by some and so allow lowering the front. the mod imply turning a bit of the outer tube surface at the point where it have a stopper for the handlebar boss. actually this stop is a raising in external diameter of the tube. If I true the tube down to the same size it have at the triple, it can slide throw the boss and the goal is achieved. the question is by which amount I should allow the fork to being slided? I mean how much you consider enough to lower the front? I know the bike have 120/70 front and 180/55 rear and so is about 6mm higher front and 2mm lower rear, so to regain the stock balance i should do 8mm height turning the fork to allow for 8 mm sliding of the tube throw the upper triple, but I have think to have it more like 12 or 15mm and have built some 4 or 5mm spacer to try different lowering setup. which you consider the max amount i should go no further? I dont want to make too much, cause for street use i think 10-12mm is enough, but maybe 15mm allow for more lowering if it is necessary. I dont have experience with lowering the front so i cannot have an idea of which size is enough...<br>pic here <!--EZCODE AUTOLINK START--><a href="http://communicator.discoremoto.virgili ... <!--EZCODE AUTOLINK END--><br>thanks canap<br>btw the racetech spring are top quality and have detailed instruction and lot of spacer, also you can choose in all strengh by .05 kg/mm increment up to 1kg/mm I think. there is a cool soft in the site you can use to have the right spring rate for your bike and your weight. bought mine here them have cheap price <!--EZCODE AUTOLINK START--><a href="http://www.psawonline.com">www.psawonline.com</a><!--EZCODE AUTOLINK END--> the spring size for 91-96 fzr is 35x33x340 and are one cm longer than the stock spring...I fitted ohlins spring last year and is shorter than the stock spring and dont have enought strengh to last long.....definitively im not satisfed with them. <p></p><i>Edited by: <A HREF=http://p072.ezboard.com/bexupbrotherhoo ... canappa</A> at: 5/12/05 1:58 am<br></i>

dragracer1951
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Re: fork mod

Post by dragracer1951 »

Canap<br>I'd think you are right on the money and that 15mm would be sufficient. You'll want to send the tubes back out and have them anodized though...<br>Ya don't want them to corrode<br>Jim<!--EZCODE EMOTICON START :cheers --><img src=http://img.photobucket.com/albums/v209/ ... Cheers.gif ALT=":cheers"><!--EZCODE EMOTICON END--> <p></p><i></i>

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creed12r
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ride height

Post by creed12r »

<br> Another alternative is to have the required amount of metal milled off the handlebar boss thereby allowing the fork to slide further up into the top yolk, if I was attempting this mod that is the route I would take.<br> Although lowering the front will give you ground clearance issues, shortening the dog bones and raising the rear is the preferred and more common mod.<br> regards<br> chris <p></p><i></i>

canappa
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Re: ride height

Post by canappa »

thanks for the reply guys, ok 15mm is what i will do Jim, at the end with a couple 5mm spacer I can vary the front height to find what work best for me. <br>about the other idea (mill the handlebar boss) had think that too, but once you mill it by 15mm there is a problem with the fitting of the rubber joint that separate the boss from the fork tube, the boss have a shape inside to accomodate the rubber joint and replicate it after the milling may be tricky, have to ask the machinist if this can be done easier, will post a pic of the boss just to show how it look internal.<br>about the shortening the dog bones this is a trial and error and a short but not always succes way, lowering the front is much better and more stable, if you make the bike higher rear is not the best thing since the bike problem is having the front higher than normal already due different tire size than stock. also this may change the ratio lever at the rear shock. well i know its the more common way now but im sure i will get better result lowering the front, and using the spacer to find the best height. <br><br>thanks<br>canap <p></p><i></i>

SimonV
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Re: ride height

Post by SimonV »

Good post Cannap - I'm thinking it's time for new springs up front - after 40k miles think they've had their day, even with max preload I'm running out of travel, doesnt help weighing 220lbs <!--EZCODE EMOTICON START :rolleyes --><img src=http://www.ezboard.com/images/emoticons/eyes.gif ALT=":rolleyes"><!--EZCODE EMOTICON END--> and based on the racetech software I need 1.00kg/mm rated springs to match my weight - stock is way below this... now to find a good UK supplier......<br><br>Simon <!--EZCODE EMOTICON START :cheers --><img src=http://img.photobucket.com/albums/v209/ ... Cheers.gif ALT=":cheers"><!--EZCODE EMOTICON END--> <p></p><i></i>

drcn
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Re: ride height

Post by drcn »

<!--EZCODE LINK START--><a href="http://www.esling.btinternet.co.uk/maxt ... <!--EZCODE LINK END--><br><br>Check out these guys, they should be able to satisfy your needs. I intend to use them to rebuild my suspension. <br><br><!--EZCODE EMOTICON START :cheers --><img src=http://img.photobucket.com/albums/v209/ ... Cheers.gif ALT=":cheers"><!--EZCODE EMOTICON END--> <br>David<br><br> <p></p><i></i>

canappa
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Re: ride height

Post by canappa »

well I checked the handlebar boss (havent made pic yet), and think is impossible to remove 15mm material without have a really unstable handlebar, the size is about 30mm total, so it will be about 15mm after the milling....that is no good to keep it stable enough since its no made like the actual ones that have a bolt to hold it against the fork tube. <br><br>I have to make a spring tool compressor, but looking at the racetech ones is easy to duplicate it....<br><br>about the parts: paid about $95 for the spring at the shop listed in my above post, them shipped to me to italy without problem, anyway since them dont carry the racetech bushing (you really want to change them stock too) and the racetech oil (10wt) I was in need, i found a shop in the UK, that is a recetech reseller, so you can get your need from them: <br><!--EZCODE AUTOLINK START--><a href="http://www.pdq1.co.uk/index.htm">www.pd ... <!--EZCODE AUTOLINK END--><br>them have all from spring to valve, bushing, oil etc. dont think you need the gold valve. new springs of the right rate, the 10wt oil, and new bushing is enough to have a well working forks. <br><br>The reason I got my gold valves is: ebay for only $50....and them are brand new.......there is also a vcr that explain how install them, I think i should make a divx from it and give to JJS to put in the ftp......that help a lot in working with usd fork.<br><br>canap <p></p><i>Edited by: <A HREF=http://p072.ezboard.com/bexupbrotherhoo ... canappa</A> at: 5/12/05 3:35 pm<br></i>

SimonV
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Re: ride height

Post by SimonV »

canap - thats UK shop is just a 10 minute drive from me <!--EZCODE EMOTICON START :banana --><img src=http://img.photobucket.com/albums/v209/ ... ananna.gif ALT=":banana"><!--EZCODE EMOTICON END--> might stop by there next week for a chat<br><br>Cheers Simon <p></p><i></i>

canappa
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Re: ride height

Post by canappa »

disassembled completely my forks, I have the pics, and had built a fork spring tool that work very good, pics of it too, now im installing the new goldvalve and springs, it is not such difficult job but you have to do it with the right tool......<br>that in my opinion are 1 fork spring compressor tool, seal driver tool, and maybe a fork cartdrige holding tool (a pipe with a 24mm nut welded over one edge), all can be selfbuilted, but maybe the seal driver is the hardest and most important to not ruin the seal and the bushings when installing them. <p></p><i></i>

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