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Fork dive

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Can excessive fork dive when using the front brake hard be lessened by increasing the oil level? Trying to avoid another internal trip. Thanks.

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it will help under very hard breaking but not much else

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The IC sping will also keep it from diving as much during the 1st few inches.

Tuners have employed THREE different IC springs with no real world difference. Each tuner has a "pkg" that he believes in and I understand that. BUT, in my quest I have either soft, mushy or stiff, deflecting action. I just really do not believe that this frame/fork design is so off that a happy, raceable happy medium does not exist. With current valving pkg and .45 springs the bike is up in the stroke, will not settle into a turn. At all. With same valving and .44 springs and 20cc lower oil level it instantly goes mushy and collapses on hard front braking. Rear wants to bury the front in whoops.After $2000 plus and lOOOOOng detailed talks with four tuners I am still without a bike I can CONFIDENTLY race. I have used mx bikes modded for woods use since '86 . EVERY single one a Honda CR250. One more adjustment and then................................... Thanks for listening guys.

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Tuners have employed THREE different IC springs with no real world difference. Each tuner has a "pkg" that he believes in and I understand that. BUT, in my quest I have either soft, mushy or stiff, deflecting action. I just really do not believe that this frame/fork design is so off that a happy, raceable happy medium does not exist. With current valving pkg and .45 springs the bike is up in the stroke, will not settle into a turn. At all. With same valving and .44 springs and 20cc lower oil level it instantly goes mushy and collapses on hard front braking. Rear wants to bury the front in whoops.After $2000 plus and lOOOOOng detailed talks with four tuners I am still without a bike I can CONFIDENTLY race. I have used mx bikes modded for woods use since '86 . EVERY single one a Honda CR250. One more adjustment and then................................... Thanks for listening guys.

dude, if you were out here, i would love to take a stab at those forks. with all of the stuff you've done to them, i can't believe they're still that far out of where they need to be.

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dude, if you were out here, i would love to take a stab at those forks. with all of the stuff you've done to them, i can't believe they're still that far out of where they need to be.
Thanks, I really am at wits end. But I have had great luck with the bike before I went looking for "perfect" suspension. Either/or, I just don't get it the huge swing in action with relatively small changes is spring rating and oil level. Thanks again.

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Just tried something------------------------------------------------------------to po'ed right now to converse intelligently. later.

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OK, I'll try again. TRIED to add 10 cc's oil to forks thru air bleed screw opening. Oil WILL NOT go in. PERIOD. Forks extended, nothing to stop flow other than air. Oil simply fills hole opening and runs all over top of fork cap creating mess. Even letting oil drip very slowly does not work, it just WILL NOT enter fork. Pray for me!!!!!!!!!!!!!!!!!! Possibility I will be on the evening news, could be real ugly. :worthy::thumbsup::worthy::ride:

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compress the fork a little then use the fork returning to suck the oil in. Also you can use the little o-ring off the air bleed screw to help seal the syringe.

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compress the fork a little then use the fork returning to suck the oil in. Also you can use the little o-ring off the air bleed screw to help seal the syringe.
I see a minimum need of four hands for that process. Will have to get back to you. Thanks.

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Actually you don't have to compress it too much. Bike under its own weight ought to do it. Just pull up on the bars and the fluid should suck in without you pushing the fluid with a syringe.

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I firmly believe that 99% of all tuners are full of crap. I've gone through 3 tuners myself, all giving me input, blaming my riding ability, blaming each other, etc. I get on another friends IDENTICAL bike and have none of the problems my bike has.

Anyway, in the process I gave up having other people working on my forks in favor of learning myself. What I discovered is three variables which should be taken into account and they are all just as important as one another.

You already mentioned the two basic ones; spring stiffness and oil level. But preload is also critical. Nobody seems to have or mess with the preload spacers, but I do!

When I work on my forks, I pull them out of the bike, even to subtract or add oil. On the dual chamber WP forks you can't suck oil out without popping the cap off. So I usually dump the oil out, pull the spring out, adjust the preload or change the spring, put new oil in and go to town. I also know what oil levels work in my fork (350 - 360cc) and that helps a great deal as well. At least thats one variable I try to leave alone (I've tried all sorts of variables).

You can take a .44 spring that might be a bit on the soft side, add one 2mm spacer and using the same oil level, not bottom out. I find oil level only makes a difference under heavy braking and more importantly, if you make a mistake and flat land a big jump, having it NOT bottom out is very nice. I tend to build my suspension so I don't bottom out because to me, thats almost more critical then anything else.

But lets go backwards for a second, you might have some valving/shimming issues as well. I honestly firmly believe in the stock setup on most modern forks, I think you can dial the stock valves in very well if you know what your doing. When was the last time someone put new oil into the inner valve chamber?

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What springs were/are used? Were they actually rate tested? If not the .45's may be .46's and the .44's may be .43's and your actual change is huge.

Why not try a split spring setting? .45/.44.

Why not test one change first? AKA dont change springs and a HUGE oil height adjustment along with it! While I highly doubt the oil height is having any major influence on your issues...it would be nice to give yourself that knowledge...and confidence that it's NOT an oil height thing.

If you don't think it turns/settle's with .45's I really don't think preloading .44's is the way to go...but it would be something worth testing for your braking issues. 2mm of preload on the .44's would make the first 30mm of travel stiffer than the .45's.

5mm preload makes the .44's stiffer than the .45's all the way to about 90mm of travel.

If trying the preload route, I'd work in the 2-6mm range if using the .44's.

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Tye, I understand your frustration but all but one of the tuners I have dealt with have been very nice guys trying their best. Yes, some of them do have their own personalities and large(sometimes fragile) egos. I really appreciate their efforts in a career that obviously can be VERY frustrating. Each has a body of knowledge gained thru many hours of testing, riding etc. they have earned the hard way. They may have differing degrees of competence but (for me) all have tried their best to help. I fully understand and applaud your willingness to take the bull by the horns and do your own work. Thanks for your tips, I do appreciate it. :thumbsup: And Mr. Harris, thanks to you. Again. I do not know if the springs have been rate tested, nor do I know if different preload has been tried. None have mentioned this to me. My continuing question is why my fork sag number is 2.25 inches, isin't that indicating a slightly stiff spring rate? Rear 5.3 shows slightly stiff also, is it loading the front too much? I just am totally frustrated that I am having such a large change in action with such small changes. Last three cr's I have used 340 cc's and standard springs with small valving changes. This bike goes very soft to very stiff with minimal change. Thanks again to all for watching my soap opera, I plan to have a line of cosmetics and lingerie out soon!!!!!!!!!!!!!!!!!

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Tuners have employed THREE different IC springs with no real world difference. Each tuner has a "pkg" that he believes in and I understand that. BUT, in my quest I have either soft, mushy or stiff, deflecting action. I just really do not believe that this frame/fork design is so off that a happy, raceable happy medium does not exist. With current valving pkg and .45 springs the bike is up in the stroke, will not settle into a turn. At all. With same valving and .44 springs and 20cc lower oil level it instantly goes mushy and collapses on hard front braking. Rear wants to bury the front in whoops.After $2000 plus and lOOOOOng detailed talks with four tuners I am still without a bike I can CONFIDENTLY race. I have used mx bikes modded for woods use since '86 . EVERY single one a Honda CR250. One more adjustment and then................................... Thanks for listening guys.

Okay, so reading this post over again. The current problem is fixed with the .45's correct? But with those .45's you can't get the bike to turn at all, right?

You may have too much trail. Your problem is starting to sound like geometry problem. With .45's on there, test certain fork heights. (Raise the forks in the clamps which lowers the front a bit. keep the rear sag in mind as well. In addition, your chain tension is important as so is your rear wheel position. It sounds to me you need someone to watch you ride, work with you one on one. Your previous tuner should do that for you. Keep working with him until you get it resolved. You've been fighting this since Feb.

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Okay, so reading this post over again. The current problem is fixed with the .45's correct? But with those .45's you can't get the bike to turn at all, right?

You may have too much trail. Your problem is starting to sound like geometry problem. With .45's on there, test certain fork heights. (Raise the forks in the clamps which lowers the front a bit. keep the rear sag in mind as well. In addition, your chain tension is important as so is your rear wheel position. It sounds to me you need someone to watch you ride, work with you one on one. Your previous tuner should do that for you. Keep working with him until you get it resolved. You've been fighting this since Feb.

Thanks jwaseman, plans in the works. :thumbsup:

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Could a slightly too stiff shock spring add to/create excessive dive when on front brake hard? 5.3 rear--.44 front, bike is stinkbuggy. Should I possibly go 5.1? Thanks.

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