Fork rake 0 degree

[Mickmorris]

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Man those things are really a pain in the ass. We have one near where I live. I have a big Ford F150, Bright Red like a fire truck. I had some 80 year old woman smash right into my passenger door. I was in the loop...she didn’t even slow down. I said lady “glad I’m not on my motorcycle OR I would be dead”. She said she didn’t see me!!! I was like WTF!!

 

[john sachs]

I can't count the # of Jap race bike chassis I've built, nor the amount of Sportster, Dyna, FXR and Softail frames, I've raked the neck of the frame on in my jig. I stand by what I said. If you use raked trees, it changes the rake, and hurts the trail. Evo Softails have 32.5 degrees of rake. That's in the trees.
John

 

[Jersey Big Mike]

I can't count the # of Jap race bike chassis I've built, nor the amount of Sportster, Dyna, FXR and Softail frames, I've raked the neck of the frame on in my jig. I stand by what I said. If you use raked trees, it changes the rake, and hurts the trail. Evo Softails have 32.5 degrees of rake. That's in the trees.
John

When you USE raked trees, you change the rake and NOT the trail. That WILL hurt hi-speed handling. 0 degree trees WILL help handling.
John

John, you are contradicting yourself a bit here.
If you change any of the parameters (front wheel size, fork length, offset etc) you effect the trail.
You as much say so about the jap race bikes , when you say "hurts the trail" The only way trail can be "hurt" is if it changes from what it was before.
In truth we are in agreement. Changing rake, trail, fork length without understanding the consequences to handling and stability can be a recipe for disater.

 

[FrankBDPS]

There have been other discussions here on this forum on this topic. I think the general consensus was that Big Dog got these bikes set up correctly from the factory.

 

[Twincam8888]

There's a reason that Superbikes have 180mm rear tires. A bike with a 250mm or 300mm rear tire will never "turn in" easily but more rake in the trees will make the steering quicker. (land ess rake in the trees makes the steering heavier but more stable at high speeds)

 

[mjsk9]

Man those things are really a pain in the ass. We have one near where I live. I have a big Ford F150, Bright Red like a fire truck. I had some 80 year old woman smash right into my passenger door. I was in the loop...she didn’t even slow down. I said lady “glad I’m not on my motorcycle OR I would be dead”. She said she didn’t see me!!! I was like WTF!!

You would hate it here in Carmel, IN Mick and Jerry! With over 132 (7 additional added since the printing of the article below) roundabouts in this 47-square-mile city with a population of 100,000 people. There are many areas where you come out of 1 roundabout and in less than an eighth of a mile enter another and this may repeat several times. I have come to love them on my bikes, kind of like "city twisties" if you get into the rhythm..... until you have a situation like you mentioned Mick and / or someone stops in the middle of them to "allow" other vehicles to enter.

The World’s Roundabout Capital Is In Indiana
If you don’t already realize it, Carmel, Indiana is known as the roundabout capital of the world. Since the late 1990’s -before most Americans ever have to drive through a roundabout- Carmel has been the epicenter of a pilot program to add them to local roads.

The city has a total of 125 roundabouts, most of which use a wide-footprint multi-lane design that routes traffic across lanes and into specific exit points. In fact, every Carmel roundabout is specifically designed to meet its exact road conditions, making each one an entirely unique traffic mover.

Carmel roundabouts are faster, more efficient and safer than other types of roadways, at least according to the city of Carmel. The city’s official position is, “They work because of their safety record, their compatibility with the environment, their aesthetics, and their ability to make it easier for pedestrians and bicyclists to navigate.”

 

[mjsk9]

That is a big circle/roundabout, some of us have circles even tighter then that as to where large trucks with trailers actually have to ride up on the circle as some of ours do not have any landscaping. To maneuver through these is to brake a little and give some throttle at the same time. Just a little more insight for you to think about.

I agree Ted..... the one pictured is huge compared to most that I am use to!

 

[mleach72]

There's a reason that Superbikes have 180mm rear tires. A bike with a 250mm or 300mm rear tire will never "turn in" easily but more rake in the trees will make the steering quicker. (land ess rake in the trees makes the steering heavier but more stable at high speeds)

So if the OP wanted to make his bike more maneuverable in the city, he would want a tree with more rake than stock, not less, correct?

 

[john sachs]

John, you are contradicting yourself a bit here.
If you change any of the parameters (front wheel size, fork length, offset etc) you effect the trail.
You as much say so about the jap race bikes , when you say "hurts the trail" The only way trail can be "hurt" is if it changes from what it was before.
In truth we are in agreement. Changing rake, trail, fork length without understanding the consequences to handling and stability can be a recipe for disater.

I probably should have said that raked trees, will cause high speed handling problems, because they upset the trail in a negative way. When the neck is raked, and used with stock "0" trees, the whole combo works together.
John

 

[Twincam8888]

So if the OP wanted to make his bike more maneuverable in the city, he would want a tree with more rake than stock, not less, correct?

Yes, more rake in the trees would make the bike more maneuverable in the city and less stable at speed. But before one changes trees use some science and calculate the change to the trail so you get it where you want it.

 

[Twincam8888]

I probably should have said that raked trees, will cause high speed handling problems, because they upset the trail in a negative way. When the neck is raked, and used with stock "0" trees, the whole combo works together.
John

Yes, raked trees decrease trail and could make a drag bike wobbly at speed.

 

[Sven]

So if the OP wanted to make his bike more maneuverable in the city, he would want a tree with more rake than stock, not less, correct?

Disclaimer: I'm no expert on the subject, formula windows, black art, but you more look at the wheel's patch on the ground. The closer it is coming towards the frame, the quicker the turn. The farther out and away from the frame, the more stable at high speed.

Say you lower the legs, or more tube past the upper crown, you shortened the steering and will turn quicker. Extend the forks out with plug extenders, the more the wheel patch is farther away from the frame.... think.

Something like the IOM TT, they run those fat tires, but when they crank it over, you can hear the rpm change via a 2nd gearing of that side wall diameter happening.

Rake and Trail

 

[mleach72]

So I have this envisioned in my head to help me understand the mechanics of rake and how it affects the bike. Maybe someone will weigh in on if my thinking is correct or incorrect.

Imagine a bike on a lift that has a long rake with a 0 degree tree. Turning the handlebars just leans the tire left and right, as opposed to a short rake that actually turns the tire. This would explain why a long rake makes turning difficult. Turning the handlebars has little input on the tire which explain the stability.

Now imagine a long rake, but a lot of it is in the tree. Turning the handlebars now swings the forks left and right. Maneuverability is increased because you are actually "bending" the bike around a corner. I can see how this would make it very unstable. Any small movement in the handlebars would violently throw the bike in the opposite direction. Do I have this somewhat correct?

 

[Mickmorris]

So I have this envisioned in my head to help me understand the mechanics of rake and how it affects the bike. Maybe someone will weigh in on if my thinking is correct or incorrect.

Imagine a bike on a lift that has a long rake with a 0 degree tree. Turning the handlebars just leans the tire left and right, as opposed to a short rake that actually turns the tire. This would explain why a long rake makes turning difficult. Turning the handlebars has little input on the tire which explain the stability.

Now imagine a long rake, but a lot of it is in the tree. Turning the handlebars now swings the forks left and right. Maneuverability is increased because you are actually "bending" the bike around a corner. I can see how this would make it very unstable. Any small movement in the handlebars would violently throw the bike in the opposite direction. Do I have this somewhat correct?

I would say that is a very good assessment.

 

[Mikeinjersey]

I would like to gain maneuverability in low speed curves. At home, there are a lot of crossroads where you have to turn, unfortunately .. It's not like in the USA with long straights.
Thanks.

Jerry,
My take on this is that Jersey Big Mike has it right " Basically -- DO THE MATH -- then have someone check your math! " Any change to any angle involved will change the Trail. Even a Big Mamma as a passenger will change it
That being said you bought a Ridgeback for a reason and it was not maneuverability. You have a Bad Ass Bike !! If you are looking to change the look of your bike that's one thing but change in order to improve handling is probably a mistake because I'm sure Big Dog did their homework before manufacturing.

 

[Jersey Big Mike]

So I have this envisioned in my head to help me understand the mechanics of rake and how it affects the bike. Maybe someone will weigh in on if my thinking is correct or incorrect.

Imagine a bike on a lift that has a long rake with a 0 degree tree. Turning the handlebars just leans the tire left and right, as opposed to a short rake that actually turns the tire. This would explain why a long rake makes turning difficult. Turning the handlebars has little input on the tire which explain the stability.

Now imagine a long rake, but a lot of it is in the tree. Turning the handlebars now swings the forks left and right. Maneuverability is increased because you are actually "bending" the bike around a corner. I can see how this would make it very unstable. Any small movement in the handlebars would violently throw the bike in the opposite direction. Do I have this somewhat correct?

Just a bit of correction.
Rake is an angle -- there is no "long rake"
The length you are referring to is the FORK length, generally measured as over stock. Although you can get shorter forks put on bikes as well.
You thought process if I understand it seems valid, just a couple misused terms is all.

Again, if you are changing frame rake, triple tree rake, fork length, wheel diameters -- DO THE MATH.
This is a classic example of why we were all taught math and geometry in school -- now's when you use it!

Before screwing with the Ridgeback, I'd consider getting a "town bike" so you can be on 2 wheels with good handling and then use the Ridge when you want to get out on the open road and cruise in style.

 

[Sven]

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[Mikeinjersey]

Seeger Cycle Chopper Kits, Have Your Dream Bike in 1 Day!

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Thank you Sven, You nailed it with this link. I advise all who are interested to take the time and read it if you would like a complete understanding of Rake and Trail

 

[jerry574]

Thanks to Sven, for the very informative link, and the others as well.
It was a question to improve handling, I'm happy with my ridgeback as it is, that's for sure. But as I am doing the maintenance of the fork, I was wondering if there was not the possibility of replacing this triple tree.