Up side down forks

everything about the chassis

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Mick P
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Up side down forks

Beitrag von Mick P » Samstag 9. Dezember 2006, 02:47

Hi
Does anybody know what up side down forks fit the Bulldog I know the top and bottom yokes will have to be changed as well.

Mick P

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Axman
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Beitrag von Axman » Samstag 9. Dezember 2006, 10:19

Hi Mick,

a year or so ago we had a thread here in the forum with a link to an finnish (or was it swedish??) Yamaha dealership that did a lot of customizing specially to the Bulldog :shock: (sorry, but I can´t find this particular thread anymore)

All their Bulldogs had USD-Forks!!

So I called them....but they had only one guy who spoke...well, I really don´t know what he spoke, but his boss thought it was english :-D

It took us a while (as gesticulating on the phone isn´t an issue :? ) but at least we came to the understanding, that they used Yamaha R1 forks (probably because the R1 and the Bulldog use the same brakes...one thing less to modify) When I asked him about the triple-clamps (or yokes) I lost him copletely.. :(

Whether the R1 yokes fit the Bulldog I don´t know, but maybe your friendly Yamaha-dealer does??

You probably could use any USD fork, providing it has the same length when collapsed. If it is too long you can always push it up in the Yokes. And that exactly is the problem : the yokes..they have to provide exactly the same rake as the original ones..a few degrees more or less make a huge difference...and a nervous or twitchy Bulldog is something I can do without..

Personally I don´t like USD forks because in my opininion the disadvantages far outweigh the advantages... it is such a hassle to service them...even for a simple oil-change you have to dismantle the front end and take them apart...

If I had my druthers I would put a set of Marzocchi Magnum RSU forks on my Bulldog (I know that they are Moto-Cross/Enduro forks, but you can always shorten the springs :wink: )they are arguably the best and plushest offroad forks ever put on a bike (and KTM only switched to WP USD forks because they own the Company)

But if your funds are unfathomable Öhlins can provide you with their new range of RSU forks...I saw them at the Motorcycle-Show in Cologne and was absolutely smitten...by the price : for 2.498,00€ they are yours and yes, the yokes come extra.. :shock:

Keep me posted..

cheers

from the Axman

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Maddog
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Beitrag von Maddog » Samstag 9. Dezember 2006, 11:06

Hi Mick,

look into trinitrin's album
album_showpage.php?pic_id=4854

He fitted a USD-fork on his dog :-D

Regards
Jürgen

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Axman
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Beitrag von Axman » Samstag 9. Dezember 2006, 13:39

Hi Mick again..

you probably saw Trinitrins bike in Willingen..(no, he didn´t ride it, he brought it on a trailer :shock: )

Trouble is, he didn´t fit the forks himself, he let someone else do it...that´s why he could´nt answer my questions regarding the yokes...the only answer I got was, that they were "custom-made" hmmm..

And as he would´nt let me ride the bike I left it at that.

Cheers

from the Axman


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Mick P
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Registriert: Montag 20. September 2004, 20:13
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Beitrag von Mick P » Samstag 9. Dezember 2006, 21:41

Thanks for that Guys

Yes your right Axman I remember seeing the bike at Willingen and I agree USD a pain to service but I am not after new and I know nothing about Moto-Cross/Enduro bikes and I suppose it would be hard to get a used pair. But there is one comment you have made that has confused me but that's not hard,
the bit about the length when collapsed I suppose there is a simple reason but I would have measured the ride length and probably made a fool of my self.... so if there is a simple explanation would you please tell me as simply as possible plus I suppose if you do the front you should really do the back. As you have guessed by now I know very little about suspension so any advice is a bonus.

Many thanks Mick :notworthy:

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Axman
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Beitrag von Axman » Sonntag 10. Dezember 2006, 10:36

Hi Mick,

a "simple" explanation is difficult because the matter at hand isn´t simple.. :?

You are right, both measurements are important - when collapsed and when extended (you have to make sure, that there always is enough overlap in the stanchions!!)

The forks that you are planning to put on your Bulldog have to come from a bike with approximatly the same weight (or have the possibility to change the springs) because after fittig the forks the bike has to stay level. When you then sit on the bike, both ends have to compress equally fast and when you dismount it has to rebound the same way.. (a simple way to test this : have someone hold your bike upright by holding the handlebar..now put your hand on the seat - where you usually sit - and push..both ends of the bike should move exactly the same way..as far and as fast)

Why don´t you give me your adress, then I´ll send you a brochure from Wilbers (a suspension company from which I got my fork springs and the rear suspension) they explain in minute detail what the suspension on a bike does..everything from progressive springs to adjustable damping..

cheers

from the Axman


Topic author
Mick P
Beiträge: 116
Registriert: Montag 20. September 2004, 20:13
Wohnort: Rochester, Kent. UK

Beitrag von Mick P » Sonntag 10. Dezember 2006, 22:51

Thanks again Axman

I didnt think there would be a simple answer i will send you my address

Regards Mick

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