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Sparky!!!
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Discussion Starter #1
OK, here is my over all plan...
I want to drop the rear of the bike about 2" and raise the front about an inch while giving it a meaner Rake....I K now how to lower the rear...but how do I lift the front...any body know of some longer tubes from another bike that will work on these bikes to give me the needed length? also as far as giving it a rake...I understand that this is not going to be an easy chore...but my buddy has a jig that we are going to put my frame onto so we can cut the neck off and re weld it on at the desired angle...I just need to find out what tubes i need before cutting so i can determine the angels at which to re weld the neck onto the bike.
 

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Sparky!!!
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Discussion Starter #3
you haven'
t read my other threads glen..i have 3000 total to spend on the bike..spent 1000 on the bike itself...and i cant justify throwing 1800 plus s&H at the forks alone....And as far as having them built for me that is also going to add big money...


Let me restart this hole topic...I am building a true chopper out of my bike. I am going back to the oldschool ways before every one and their brother started making custom parts. I am Building and fabing everything my self. All parts bought for this bike HAVE to be stock from another bike and have to be able to be found from a used scource... My over all goal is to have a $30,000 looking bike for $3000.
 

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Forks by frank are cheap all things considered, i'd take a look at pricing on JUST the uppers. You dont need to by the whole front end. The other place you might be able to find longer forks is off a dirt bike.

When I chopped My honda, I lowered and hardtailed the rear, and then raked the front by stretching the downtubes and backbone. I tried to go with stock fork tubes. but ended up trading for a set of 2 over forks off a different bike.

Another option would be to run a taller front wheel.

Total price tag on my Honda ran 1900.00. Including the inspection and registration
 

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Ducks right, I haven't bought a set of tubes from Frank's in quite a while, but they make quality stuff. I'm thinking around a couple hundred bucks or so will get you a set of 4130 Chrome Molly upper tubes, any length you want, a direct R&R, just unbolt the lowers and install on the new tubes. Or find some longer 38mm forks off a dirt bike.
 

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Sparky!!!
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Discussion Starter #6 (Edited)
thanks guys..i have been doing some more research on the neck to find a triple tree that is compatible wit our neck. so far no luck..

I am looking for the thread that contained something about a reverse parts look up....can't remember where i saw it...it was just posted within the past few days though. With the Revers look up along with the inside DIA of our necks i should be able to put all of this information to good work...

Thanks for the stock tube DIA just in case i need to go that route as well

well found out a lot of good stuff...first off I found out that a KZ1000 LTD uses the same Triple Tree as ours... also found out that the 1987 A1: VN1500 uses a different triple tree, but the stem uses the same bearings as our smaller bike... so now i am in wait of two emails...one from a guy with forks off of the KZ1000 LTD to see if the forks are longer (and how much longer) than the VN 750, and a second email from a guy with the VN1500 whole front assembly to find out if those forks are longer and to determine the length of the stem to see if it will match up to mine.

How do you measure the stem to determine if it is going to add or subtract rake angle when installed? If the whole setup for the 1500 is going to add some rake i might go that route for now and add stretched tubes later down the road...
 

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Most stock trees are built with no additional rake. Most experts will tell you not to use raked trees until you hit rakes of 40 deg or more, and then only to adjust your trail.
Increasing the length of your forks will raise the front end, increasing the rake and trail. Using longer forktube and raking the neck without raising the neck will also increase your rake and trail. Also Lowering the rear of the bike increases the rake.
My honda went from a 30 deg rake to a 36 deg rake, just be stretching the front frame downtubes 2".

Don't forget to measaure the length of the stem on the forks you want to use. If the stem is too short for your neck, you won't be able to fit the bearings, same goes if the stem is too long.

A favorite trick among chopperheds is to remove the stem from your stock tree and weld it into your new trees. This is commonly done to use Harley front ends on Jap bikes.
 

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Sparky!!!
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Discussion Starter #9 (Edited)
Hey duck...good idea about the stem...never thought of using my old stem...what about using the neck off of another bike that i would be using the triple tree from??

next quest what did you mean by racking the neck without raising it? my plan is to cut the neck off the bike where the down tubes meet the spline. Also I will cut off the neck braces and build new braces weld the braces back onto the frame fallowed by re welding the neck onto the braces...the new brace would have the desired angle worked into it.

How much work would be involved stretching our Down Tubes?

one last question...after reading the article that Duck gave us on calculating rake...it looks like if i want to cut off the neck and re weld it with more rake involved then i will need a raked set of triple trees to offset the trail... am i thinking on this correctly???
 

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Hey duck...good idea about the stem...never thought of using my old stem...what about using the neck off of another bike that i would be using the triple tree from??
Since most states and provinces register bike of the neck numbers, its easier to change out the stem.

next quest what did you mean by racking the neck without raising it? my plan is to cut the neck off the bike where the down tubes meet the spline. Also I will cut off the neck braces and build new braces weld the braces back onto the frame fallowed by re welding the neck onto the braces...the new brace would have the desired angle worked into it.
This would be the best way,

How much work would be involved stretching our Down Tubes?
Too much to be worthwhile, because of the removeable frame section. I have another way figured out that should be easier

one last question...after reading the article that Duck gave us on calculating rake...it looks like if i want to cut off the neck and re weld it with more rake involved then i will need a raked set of triple trees to offset the trail... am i thinking on this correctly???
If you rake past 40 degrees or so and your trail measures up to be too much, raked trees can help bring it back in line. It depends on how mych trail you end up with
 

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Sparky!!!
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Discussion Starter #11
OK. I ran the numbers and came up with 45 degrees total rake. So I need 7 Degree Triple Trees to bring the trail from 10.XX inches back to the stock 5.00 inches. Now going with the idea of using a set of HD triple trees, if I am reading the measurements right I can adjust the offset by moving the stem when I weld the stock stem to the triple. Also is the Rake on the triple tree determined by the angle in which the stem is attached to the lower fork holder? And if so is a 7 degree raked triple tree stem mounted at 7 degrees in association to the lower fork holder?
 

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I don't see how that will work. Most triple tree stems are parallel with the fork tubes. By adding a 7deg. rake to the lower triple tree, by welding the stem at that angle. How are you going to mount the top? Make a top with a center hole offset enough to make up for 7deg bottom?
 

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OK. I ran the numbers and came up with 45 degrees total rake. So I need 7 Degree Triple Trees to bring the trail from 10.XX inches back to the stock 5.00 inches. Now going with the idea of using a set of HD triple trees, if I am reading the measurements right I can adjust the offset by moving the stem when I weld the stock stem to the triple. Also is the Rake on the triple tree determined by the angle in which the stem is attached to the lower fork holder? And if so is a 7 degree raked triple tree stem mounted at 7 degrees in association to the lower fork holder?
Adjusting the Offset is not a simple thing. you are pretty much stuck with the offset and rake that are built into the trees. The stem is pressed into a bore in the lower treee and then welded around the bottom. To adjust or change the offset you would have to weld up the original stem hole and the have it rebored to the size you need in a new location or have a billet tree made.

7 degrees in the trees is a lot. You might have to adjust a bit and deal with a bit more trail and run a 5 degree tree. although, By the time every thing is said and done, you'ld be cheaper to build a springer to fit. A custom set of raked trees will run 4-5 hundred bucks. not low budget when you add in the cost of longer fork tubes and the labor of the fork rebuild. .

Raked trees are measured in relation to the neck of the frame. A zero degree set of trees adds no rake to the rake of the frame.
A 5 degree raked tree would have an additional 5 degrees over the rake built into the frame.

Please note that merely lowering the rear of your bike 2" can change the effective rake several degrees.
 

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I don't see how that will work. Most triple tree stems are parallel with the fork tubes. By adding a 7deg. rake to the lower triple tree, by welding the stem at that angle. How are you going to mount the top? Make a top with a center hole offset enough to make up for 7deg bottom?
Yep pretty much it.

When they make a set of raked trees, they have to sit down and do the math and figure out before hand how much they have to offset the stem bore. The lower treee will be machined with a stem bore that is offset and angled slightly, to match up with the top tree which has been machined to a different offset and machined with an angle to match. However, as soon as you change th distance between the trees, you change the geometry, and nothing lines up. Raked trees have to be built for the bike they are to be mounted on, or at least something with the exact same Neck dimensions.
 

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Sparky!!!
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Discussion Starter #15
Yes i know that lowering the bike is going to change my rake...that is why i am going over all these numbers and trying to figure out what the best deal is going to be...I want to have a total rake of about 40 degrees, while keeping the trail as close to 5 inches as posable.

Dumb question...whats a springer front end? does it look like this?


if so...would i then use my stem to make it match up? same as we were talking about b4 with the triple tree?
 

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That there is a girder front end, deemed my many old pros to be the best thing there is fro adjustability, and tuning. You could change out the stem and make it work, if its long enough. The big thing to watch is the distance between the trees. With a girder, you want the links to be as parrallel as possible to ensure good operation. If the trees end up being to far apart or too close together, the geometry will change. HOWEVER, Adjusting link lengths can change handling and steering characteristics immensely. This is why they are so tuneable. You can change the link arms to get whatever rake you want, but you have to watch out for geometry issues.

A springer front end is a bit different, but also very tuneable. The springer uses a rigid fork set, with a rocker arm bolted to the forks and a secondary fork set generally capped with a pair of springs on top. With springers, the rockers are what give you your adsjustability.

Go here for more info
http://www.hotrodcitycustoms.com/forks.php
 

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Sparky!!!
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Discussion Starter #18 (Edited)
how do i change the stem? to work with the grinder...


Now on to Springer Questions...how does the springer front install??? does it use the OEM Triple tree, now you guys are confusing me...lol
 

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On the bikes Ive played with the stem is pressed into the lower tree and backwelded to hold it. Usually all you have to do is grind off the weld and press the stem out.

Then,

The stem bore in the tree has to be matched to the stem, The assembly is pressed together and the stem is backwelded to the tree.You do have to watch the upper to lower tree distance ( stem length) If you have a bike with a 7.5" neck, and you install a 8" stem, the bearings wont fit. The same bike with a 7" stem won't work either, I always measure form the top of the fork tube to the axle, not the bottom tree ( like HD). If you install a set of forks, with a shorter stem on a bike needing a longer stem, the difference has to be accounted for.

The reason...

If I go out and measure by forks from the axle to the top of the fork, I get a measurement.

If I measure from the axle to the bottom of the lower tree, I get a different measurement,

Heres where it gets complicated.

I have a bike, it mesaures 30" from the axle to the lower tree. This is a standard HD measurement. Lets say The HD has a 7" stem length. So, if I figure in the distance form top to bottom tree, and thickness of the trees, i get a total lenght of about 39" That gives me 39" from the top of the fork to the axle centerline. Now that is a fork set at standard length.

If I buy a 4" over forkset, the distance from axle to tree increases by 4", both to the bottom tree and the top of the fork tube.

However, When I install that same forkset on a bike with a 9" neck, I run into issues. The axle to top of fork tube length doesn't change. but if the lower tree is now 2" lower than the original tree, the axle to lower tree length changes by 2", I now have only a 2" over forkset. Since I had to lower the bottom trees to compensate for the change in tree length, the actual distance between the axle and the lower tree is now only 32"

I hope this makes sense


The keyboard has been drinking.
 

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Sparky!!!
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Discussion Starter #20
yup sure does....So i just need to take my stem off of my triple tree and then get the new triple tree machined to fit my stem and re weld my stem onto the tree....but where I am getting confused is why do I have to worry about the distance between the upper and lower fork holders? wouldn't me shortening the or lengthening the tree do this by itself? also thinking about going with the grinder...it does look like a much simpler set up and one I could mod my triple tree to it easier.
 
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