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Discussion Starter · #1 ·
I just finished modifying this old Jamis Dakar frame and fox fork for a bud and lou.
Widen the rear triangle for 190 hub and a 5" tire.
Widen the BB to a 100mm installed a race face 190 crank
Widen a fox fork for a 135 mm hub and a 5" tire

I rode it about 20 miles or so, it handled very well on the hard pack trails no negative effects from the bigger tires. It rides like a mountain bike, quick handling. When I modified the rear triangle I keep the chain stays as short as possible. But when you ride it in the mush it also rides like a mountain bike except for the float. It does not have tracking the a snow bike has.
The fork works awesome with the wide tire. A lot of horse tracks in the trails the full suspension with the big tires made it so you could fly down the trails. Over all a fun bike to ride can't wait to put some more miles on it.

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Discussion Starter · #4 ·
:QUOTE=ShartRate;11085332]Glad it's working so far, just hope you have your insurance paid up just in case![/QUOTE]

Well if a bike part failing on me is the biggest thing i have to worry about just call me a puss and shoot me.:rolleyes:
 

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Discussion Starter · #8 ·
Well done sir.

Edit: the fork does scare me some, maybe a person could reinforce it with carbon or something.
I did reinforce it by doweling in a piece of alloy into each side of the bracket then welded it into the bracket before i built up the differents. I did some wheel stands on it around the shop seems to be pretty stiff but only time and abuse will tell. the dowel in piece will should keep it from being a catastrohic failure:skep:
 

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I did reinforce it by doweling in a piece of alloy into each side of the bracket then welded it into the bracket before i built up the differents. I did some wheel stands on it around the shop seems to be pretty stiff but only time and abuse will tell. the dowel in piece will should keep it from being a catastrohic failure:skep:
Cool that's the stuff I like to hear/see that was kind of left out of the original post. Love innovation!!
 

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Discussion Starter · #10 ·
Cool that's the stuff I like to hear/see that was kind of left out of the original post. Love innovation!!
Yes, there is quite a bit of head scratching to make it all work. I don't advocate running down to the box store buying a hacksaw, a welder and getting after your 2000 dollar bike without a plan.
No guarantees what I have done will work out, after a 1000 miles I would call it an success. But it is a fun project I paid 200 dollars for the frame and shock about 100hrs in labor. I am not a machinist or welder just have basic skills, like to build things and have fun doing it. But its best when you can have fun riding it.
 

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Ummm....

That fork is just a fright. I make LOTS of stuff for all kinds of applications, but sorry, I would NOT encourage anyone to copy this. I don't fault people for thinking about it, but unless you REEEEEEEEALLY know A-F-ING-LOT about metallurgy and TIG welding, you are just asking for a revised face. Even if this "works," I still wouldn't!

As a for-instance of the potential complications, the manufacturers have a real habit of using alloys that ARE NOT WELDABLE. If you are not aware of that, then....
 

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Ummm....

That fork is just a fright. I make LOTS of stuff for all kinds of applications, but sorry, but I would NOT encourage anyone to copy this. I don't fault people for thinking about it, but unless you REEEEEEEEALLY know A-F-ING-LOT about metallurgy and TIG welding, you are just asking for a revised face. Even if this "works," I still wouldn't!

As a for-instance of the potential complications, the manufacturers have a real habit of using alloys that ARE NOT WELDABLE. If you are not aware of that, then....
Agreed, this is downright scary. After cracking many xc frames in the 90's before they built real aluminum mtn bikes that could take a beating (and when we learned xc bikes were not meant for trials and freeride), you learn these frames really aren't re-weldable due to heat treating issues.

A+ for effort, but I suggest you suit up like Bender did for the Jah-Drop. I would hope no one copies this, but it brings back memories of all the young kids who used to cut bikes up and "modify them".....good luck, stay in one solid and undamaged piece.
 

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Ummm....

That fork is just a fright. I make LOTS of stuff for all kinds of applications, but sorry, I would NOT encourage anyone to copy this. I don't fault people for thinking about it, but unless you REEEEEEEEALLY know A-F-ING-LOT about metallurgy and TIG welding, you are just asking for a revised face. Even if this "works," I still wouldn't!

As a for-instance of the potential complications, the manufacturers have a real habit of using alloys that ARE NOT WELDABLE. If you are not aware of that, then....
I agree as well, I have had a major failure from lengthening a spindle on a crank that actually almost got me killed and that was just a crank. I didn't want to say anything because there is enough negativity on here already but this is not a good idea.

Sorry and please be safe.
 

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I still like it.

Every advance was made by some guy prepared to risk his front teeth.

However, I do share the concern about the fork crown alloy. Maybe a carbon wrap would add a bit of security.
 
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Ummm....

That fork is just a fright. I make LOTS of stuff for all kinds of applications, but sorry, I would NOT encourage anyone to copy this. I don't fault people for thinking about it, but unless you REEEEEEEEALLY know A-F-ING-LOT about metallurgy and TIG welding, you are just asking for a revised face. Even if this "works," I still wouldn't!

As a for-instance of the potential complications, the manufacturers have a real habit of using alloys that ARE NOT WELDABLE. If you are not aware of that, then....
Agreed, this is downright scary. After cracking many xc frames in the 90's before they built real aluminum mtn bikes that could take a beating (and when we learned xc bikes were not meant for trials and freeride), you learn these frames really aren't re-weldable due to heat treating issues.

A+ for effort, but I suggest you suit up like Bender did for the Jah-Drop. I would hope no one copies this, but it brings back memories of all the young kids who used to cut bikes up and "modify them".....good luck, stay in one solid and undamaged piece.
I agree as well, I have had a major failure from lengthening a spindle on a crank that actually almost got me killed and that was just a crank. I didn't want to say anything because there is enough negativity on here already but this is not a good idea.

Sorry and please be safe.
That fork is terrifying.
From a guy that enjoys the tinker/tweek aspect of life this project is appreciated but thats where it ends ( a person must know their limitations) and could not agree more with the above quotes.
 

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exp18 I hope you can appreciate we are not trying to diss on your want for being creative and resourceful. I totally get where you're coming from, I am working on a full suspension design as we speak (well, that's a lie, I've been spending time making a heated partition in my garage to prepare to continue working on a full suspension frame, because part of the process involves maintaining an ambient room temperature for several hours in the dead of winter).

In other words: chop chop is fine by me.

But... we just don't want a brother to get messed up, I'd sooner have you consider me an ******* than have you get hurt. The post-weld concerns for aluminum are very real. I'd revisit that crown. I'd suggest using carbon fiber, but then that's my material of choice, and you know, when you're holding a hammer, everything looks like a nail.
 

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Discussion Starter · #20 ·
You guys are to funny, the only thing that is terrifying is how good it works and how have a full suspension holds the trail. It makes the trees fly by pretty fast, now that's a little terrifying.
I appreciate the useful input and the genuine concern that I may have over looked something. I may have overestimated the strength in my fork but I don't think so, time will tell. But that will not keep me from having fun with it, to me I see more risk in setting on the couch. To each their own. For the others I guess that why the good old World Wide Web, Pro Sports, Beer and the lazy boys was invented so you can arm chair quarterback with no good input or clue. Do you really think I did this with no clue Ralph??? Oh I take back the beer part!

Onto other things, I was not a believer in FS fat bikes when I started this. I was going to build it for 29+ wheels but thought I should make the frame wide enough for a 5" tires when it is real muddy and soft out. But it has worked out great, I like the mountain bike geometry for the packet trails was out last night for about 20 miles it handled the single track and bumps unbelievable. Don't get me wrong if you are riding new snow or mush your snow bike geometry will be way better.
Can't wait to get my 29+ velocity loops so I can build them up for summer.:thumbsup:

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