How dumb is this idea?

dude, just get some low bend pro tapers and call it a day, you'll never bend your bars again and never have to buy any bars ever again.

I had protapers on it

Thanks for bantering with me... and no disrespect, but i dont buy your argument.

You can not change the angle either to the ground or the bike, the angle is fixed.

We are not going to agree on this one. I know because i have done it to my moto and you can see the difference in the angle. I raised the tube in the triple tree and you can see the fork angle change. Try it yourself! I did it thinking it would make the handling better and it made it edgy. I knew to try this because I know several independent bicycle manufacturers and worked at a mountain bike shop for a while AND my best friend designed and welded up a mountain bike as his senior design project as an engineer. It is all about head tube angle and bike handling/ angles are common to moto angles.

The angle does change... It is just simple... changing the length of one leg of the tri-angle effects the angles. The angles effect the handling. Here is a perfect example, people would come into the bike shop with a super old school mountain bike and want to put a new fork on it, but we never encouraged it because new forks are longer travel so they are taller and they change the angle. People who put new tall forks on their old mountain bike always report slow steering and a DH like handling.

Yes, the wheel base does change but that is not the cause of the handling change. Re-read what i was saying about mountain bike sizes!The size changes the wheelbase dramatically on a mountain bike, head tube and handling stay the same. Anouther good example on that is the shop i worked for Boulder Bikesmith... They would do custom cruisers. They would take a steel mountain bike, chop the frame and weld in like a 8 inch section to stretch it. and the bike reacted to terrain relatively the same

One of the changes some manufacturers have been making recently, Honda for example, with motocross bikes is to change the position of the front wheel in the fork. They pull the front wheel back 10mm in the fork, this accomplishes the same thing as changing the offset (head tube angle) without changing the offset. (cheaper) It greatly affects handling.

That is what you are doing by moving the forks up.

A good example when talking about handling, but I dont agree with the reason or the cause for change in handling. What you are talking about does effect the handling but it isnt because of a change in wheel base, it is because of a change in fork rake. If you draw a line through the headset and follow it to the ground, then measure it on the inside of the bike against a flat surface, that is headset angle. What you were talking about is fork Rake. Fork rake is how far forward of back from where that line would intersect the hub. Changing the fork rake does not effect the angle one bit but it does dramatically effect handling. At the bike shop they use to build these sweet custom chopper forks but the handling could get all jacked up when they played with the fork rake too much.

If wheel base were so important than why does the handling not change throughout the life of a chain? You get a chain and your wheelbase is short then as the chain gets older your wheel base gets longer and you go on your merry way and think nothing of it.

TRUE wheel base is often discussed when people talk about bikes, but it is because the smaller wheel bases can make smaller turning radius and it effects the cornering. As far as bump stability and handling response to inputs (the stuff that makes a bike stable or unstable), that goes down to head tube angle and fork rake.

In the original post you were kicking around the idea of flipping your handle bars and was wondering how it would affect the handling.

The biggest change will be your body position. Instead of a balanced reach you will be leaning more forward which puts more weight on front end.

My Triumph desert sled is a good example. These old Triumphs were designed to be ridden while seated. Single track, two tracks and fire roads the bike rips but finding trails that are not whooped out from modern

long travel suspension bikes" is difficult to ride seated so I had to figure a way to be able to stand on the pegs to ride sections of whooped trails.

When I stood on the pegs I could look straight down and my head was almost centered over the front axle which made everything out of balance.

It took a taller pair of handle bars to move my body position backwards while standing on the pegs to give me better over all stability.

I also took a pair of forks from an old YZ and rear shocks from an old 350 XR to gain more suspension travel and ground clearance.

In the original post you were kicking around the idea of flipping your handle bars and was wondering how it would affect the handling.

The biggest change will be your body position. Instead of a balanced reach you will be leaning more forward which puts more weight on front end.

My Triumph desert sled is a good example. These old Triumphs were designed to be ridden while seated.

Triumphs are cool...

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Triumphs are cool...

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and fun :D

Thanks for bantering with me... and no disrespect, but i dont buy your argument.

We are not going to agree on this one. I know because i have done it to my moto and you can see the difference in the angle. I raised the tube in the triple tree and you can see the fork angle change. Try it yourself! I did it thinking it would make the handling better and it made it edgy. I knew to try this because I know several independent bicycle manufacturers and worked at a mountain bike shop for a while AND my best friend designed and welded up a mountain bike as his senior design project as an engineer. It is all about head tube angle and bike handling/ angles are common to moto angles.

The angle does change... It is just simple... changing the length of one leg of the tri-angle effects the angles. The angles effect the handling. Here is a perfect example, people would come into the bike shop with a super old school mountain bike and want to put a new fork on it, but we never encouraged it because new forks are longer travel so they are taller and they change the angle. People who put new tall forks on their old mountain bike always report slow steering and a DH like handling.

Yes, the wheel base does change but that is not the cause of the handling change. Re-read what i was saying about mountain bike sizes!The size changes the wheelbase dramatically on a mountain bike, head tube and handling stay the same. Anouther good example on that is the shop i worked for Boulder Bikesmith... They would do custom cruisers. They would take a steel mountain bike, chop the frame and weld in like a 8 inch section to stretch it. and the bike reacted to terrain relatively the same

A good example when talking about handling, but I dont agree with the reason or the cause for change in handling. What you are talking about does effect the handling but it isnt because of a change in wheel base, it is because of a change in fork rake. If you draw a line through the headset and follow it to the ground, then measure it on the inside of the bike against a flat surface, that is headset angle. What you were talking about is fork Rake. Fork rake is how far forward of back from where that line would intersect the hub. Changing the fork rake does not effect the angle one bit but it does dramatically effect handling. At the bike shop they use to build these sweet custom chopper forks but the handling could get all jacked up when they played with the fork rake too much.

If wheel base were so important than why does the handling not change throughout the life of a chain? You get a chain and your wheelbase is short then as the chain gets older your wheel base gets longer and you go on your merry way and think nothing of it.

TRUE wheel base is often discussed when people talk about bikes, but it is because the smaller wheel bases can make smaller turning radius and it effects the cornering. As far as bump stability and handling response to inputs (the stuff that makes a bike stable or unstable), that goes down to head tube angle and fork rake.

Actually lots of guys will run the wheel as far back in the adjusters as possible to increase stabilty.

The more I look at the overall picture of moving the forks up in the clamps I concede and agree :D it does change the overall geometry (between the bike and the ground not the forks and the bike)

What about the idea of mounting the clipons below the upper triple clamp. Anyone try this before?

I guess that lesson on rake and trail this morning made sense huh Rob?:D

My theory is make the mods, then take it out and pin it! No guts no glory. There are no dumb ideas, just horribly painful outcomes from these creative ventures!

I once decided to do some frame mods on an old Honda 550 four that I had years ago. I also made the incredibly lame decision to weld it with a coat hangar as I ran out of welding rod......(okay I was young!). I took it out an pinned it! It broke........I crashed hard.....2 lessons learned! I now own a tig welder, and my shoulders ache on rainy days:banghead:

Have fun with it.

Haha... thats some good input. I really want to try it but im waiting for a brake lever. I guess suzuki parts take a week to get in and im not willing to go on the road without a front brake. ESPECIALLY after my incident last week.

This SUV was slowing down and crowding the right hand side of the road, pulling over before the intersection. Obviously not sure which way to turn. I pulled out to pass, then he made up his mind he would be dramatically turning left. All i remember is leaning back and pushing as hard as i could with my arms not to go over the bars, rear wheel fully ****ing locked. The ******* actually looked at me and yelled out the window "look at my directional" as if signaling that he intended to have me T-bone him made it ok.:D

Thanks for bantering with me... and no disrespect, but i dont buy your argument.

We are not going to agree on this one. I know because i have done it to my moto and you can see the difference in the angle. I raised the tube in the triple tree and you can see the fork angle change. Try it yourself! I did it thinking it would make the handling better and it made it edgy. I knew to try this because I know several independent bicycle manufacturers and worked at a mountain bike shop for a while AND my best friend designed and welded up a mountain bike as his senior design project as an engineer. It is all about head tube angle and bike handling/ angles are common to moto angles.

What are you referring to as the "fork angle" the head tube angle is what he is reffering to and indeed this never changes, however the angle of the for in relation to the ground does change.=, and would have a similar eh=ffect to raising or lowering the rear of the bike

okay here is the definitive answer about head tube angles, rake, trail and so on.

RAKE: The angle in degrees of the steering neck from perpandicular.

TRAIL: The distance defined by the vertical line from axle to ground and the intersection of centerline of the steering neck and ground.

HOW TO MEASURE CORRECT TRAIL

Raise the bike to an upright position, using a tape measure, hold the tape straight down from the front axle to the floor. Put a mark on the floor at that point. Then place the tape parallel to the steering neck, following the angle of the steering neck all the way up to the floor. Put a mark here also. Now measure the distance between the two marks and you have your trail measurement. I just use one of those cheap laser markers you can buy at most building supply stores. With too little or negative trail (steering axle mark behind the front axle mark), the bike will handle with ease at low speeds, but will be completely out of balance at high speed. It will/can easily develop a high-speed wobble. NOT FUN!

Normal trail is somewhere between 2 and 4 inches. The bike will handle easily at both high and low speeds. Driving smoothly through the twisties without swaying or wobbling. If the trail is more than 4 inches the bike will handle sluggishly at high speeds. It will seem almost too steady. You will have trouble balancing the bike at lower speeds or on winding roads. It will feel generally sluggish and clumsy. This why choppers run poker straight so well, but are dogs on the twisties

Therefore by lowering the triple clamps on the forks, without lowering the backend the same amount will in fact alter the RAKE angle of the steering head in relation to a perpandicular axis, which will also reduce trail, possibly to the point of being unmanageable at speed.

All that being said......make the mods, then go out and pin it!

No big developments have ever been made without creative risk takers!

okay here is the definitive answer about head tube angles, rake, trail and so on.

RAKE: The angle in degrees of the steering neck from perpandicular.

TRAIL: The distance defined by the vertical line from axle to ground and the intersection of centerline of the steering neck and ground.

HOW TO MEASURE CORRECT TRAIL

No big developments have ever been made without creative risk takers!

Big Dog! Thanks for setting me straight. My experience is in bicycles and they use slightly different names for all that. But as you pointed out here, the net effect is the same. Fortunately i have changed neither the rake nor the trail, only the weight distribution so hopefully pinning it will result in smiles rather than road rash.

stil waiting on a brake lever. And being lazy on posting photos.

Hey its all good man! The bottom line is having fun, and sharing knowledge.

I definitely want to see some pics when you are done.

My new DRZ400CR (cafe racer) has been ready to ride for a week but it was less than 40 degrees F or raining all week. Today was my first chance to try it and I really like it! The bike handles just like it did before, as we had debated. AND the body position is SO much more comfortable, especially as i had high rise bars and my saddle chopped so i was super high. Now it feels just right! It feel a lot more like a SV650 or dare i say monster 750. It was no small project as i had to jack around with the cables, directionals and the bark busters. Notice they are all sorts of mixed up. But I think it looks ok. It all functions smoothly and does not look like it will wear funny. I Need a super cool stem mount (not sure of the name of what connects the triple tree to the bars) now. Any one have a recommendation of a cool one on the cheap?

Here is the before:

L1020032.jpg

And here is the after:

L1020177.jpgL1020179.jpgL1020178.jpghttp://i442.photobucket.com/albums/qq141/calefL/L1020179.jpg[/img]http://i442.photobucket.com/albums/qq141/calefL/L1020180.jpg[/img]L1020181-2.jpg

Anyways, time will tell but so far i really like it. Also I should post on the seat cut. That was quite the project but i really like it. Im 5'6" and all torso so it really makes riding 2 up a lot more natural.

Congrats! Looks awesome....We all know now that it was not a dumb idea at all, and kudos to you for thinking outside the box!:lol:

Time to pull your man card.....

I had to laugh, I'm taking a class at Kettering, and parked out front was a spurtster that someone had done the same thing too. Made me think of this thread. The outcomes were similar.

:worthy::eek::banghead:
Big Dog! Thanks for setting me straight. My experience is in bicycles and they use slightly different names for all that. But as you pointed out here, the net effect is the same. Fortunately i have changed neither the rake nor the trail, only the weight distribution so hopefully pinning it will result in smiles rather than road rash.

stil waiting on a brake lever. And being lazy on posting photos.

Hey Calef, :eek:

Man... I wish I saw your post on the bent lever before you tried to straighten it out. If you use a propane torch and gently heat the lever, you can easily straighten it back just like new without breaking it off. I straightened one out twice before tipping over on asphalt a third time and totally snapping it off.

Something else not mentioned yet is that the combination of your cut down seat and lower bar position considerably lowers your center of gravity.

Like some others here, I also come from bicycle experience and the proper head angle is a critical to good handling characteristics. Pulling up the fork tubes steepens that angle and makes for more quick twitchy steering. Not a good thing to have on the freeway. However... lower the rear to match as well as lowering the handlebars, and you can retain the same head angle, and lower the center of gravity of both the bike and rider...

IMG_1775-1.jpg

This immensely improves the cornering stability.:worthy:

Take Care,

Greg

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