Extended front forks

TapioK

Well-Known Member
I doubt if 2" longer tubes actually make any noticeable change on leaning angle or in center of gravity. To fix leaning angle I would make higher pipes and swap pegs to something like this. I remember Jake has bmx style pegs in his Ridgeback
 

Mr. Wright

Knows some things
Supporting Member
I don't see what's wrong with a chopper for comfort, reliability or cross country trips whoever wrote that is a pudd

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I'll agree with that. I,ve been running around on a Heritage Soft Tail Harley. Customer said to put some miles on it and check it out good before he sells it to his son. I've run a couple tanks of fuel through it, and running around town and the back roads wasn't bad, but 50 miles down interstate beat me to death. I can ride my Chopper all day and feel just fine.
 

Mr. Wright

Knows some things
Supporting Member
Assuming your math is Correct , the seat or halfway from the tree to the rear axle(pivot point) that would raise the seat 3/4's of an inch , theoretically of. Course



looks like you may need to adjust the suspension on the heritage.
I think it more the wind and windshield.
 

cdogg556

Guru
2" longer tubes might actually look good on K9. I'm suprised if noone has tried it.
It may look really good, but if you change the trail of the bike and it gets over 6" you may have a really shitty handling bike, from what I have read as long as your trail is no less than 3.5" and no greater that 6" you should be ok, so I would definitely check it to see how it changes the trail of the bike. But is it really worth it? The bike looks great as is in my opinion, just leave it alone. http://www.thompsonchoppers.com/rake-and-trail-calculator/
 

TapioK

Well-Known Member
Originally K9 has 4.35" trail (Chopper has 4.7"), add 2" to tubes and you have about 4.2" Dyna has 4.1" and FLH 6.2". V-Rod has 3.87", old Hayabusa 3.8" so we are still in "safe area" steering in low speed should be a touch lighter. If you wanna make K9 just run straight change to 0 degree trees and you know what heavy steering means with 7.45 trail.
My calculations are not precise since being in Finland I cant measure the triple clamp offset (I estimated 2.8"), and I trusted my memory on factory forks being 46".
I'm not rushing to order 14 over tubes, but if I need to replace originals, it would be interesting to test...
 

cdogg556

Guru
Originally K9 has 4.35" trail (Chopper has 4.7"), add 2" to tubes and you have about 4.2" Dyna has 4.1" and FLH 6.2". V-Rod has 3.87", old Hayabusa 3.8" so we are still in "safe area" steering in low speed should be a touch lighter. If you wanna make K9 just run straight change to 0 degree trees and you know what heavy steering means with 7.45 trail.
My calculations are not precise since being in Finland I cant measure the triple clamp offset (I estimated 2.8"), and I trusted my memory on factory forks being 46".
I'm not rushing to order 14 over tubes, but if I need to replace originals, it would be interesting to test...
If you are correct on your calcs then yes it would actually still be within the "Safe zone" and should be fine, it seems strange to me how lengthening the fork tube reduces the amount of trail, seems like it would be the other way around, so I stand corrected that adding to the tubes is dangerous, as long as it is still between 3.5" and 6" of trail.
 

TapioK

Well-Known Member
If you are correct on your calcs then yes it would actually still be within the "Safe zone" and should be fine, it seems strange to me how lengthening the fork tube reduces the amount of trail, seems like it would be the other way around, so I stand corrected that adding to the tubes is dangerous, as long as it is still between 3.5" and 6" of trail.
This makes it all clear
http://www.seegercycle.com/Rake-and-Trail.aspx
So you can play with tubes, rake of the neck, rake of the tree, tree offset and you can even get neck bearing cups that have little rake to finetune... inreresting shit, if you happend to be interested.
 

cdogg556

Guru
This makes it all clear
http://www.seegercycle.com/Rake-and-Trail.aspx
So you can play with tubes, rake of the neck, rake of the tree, tree offset and you can even get neck bearing cups that have little rake to finetune... inreresting shit, if you happend to be interested.
Very cool how the end result was a bike with a chopped front end with almost the same trail as the stock bike, I just looked up the specs on my Mastiff and the trail is 4.8 inches, so how much longer could you go and still be in the safe zone? So then if I went longer on my bike it would give me less trail or more? Still a bit confusing.
 

TapioK

Well-Known Member
Very cool how the end result was a bike with a chopped front end with almost the same trail as the stock bike, I just looked up the specs on my Mastiff and the trail is 4.8 inches, so how much longer could you go and still be in the safe zone? So then if I went longer on my bike it would give me less trail or more? Still a bit confusing.
There is a program to figure this shit out, but one would need total lenght of the forks, tire diameter, neck rake, tree rake, and offset...
And still the result is a bit about... on the other hand when braking your trail easily changes 2". And other issue I didn't even mentioned is a flop of the front. When front gets longer you at some point should prevent bars turning too much or tire will "flop" making slow speed maneuvers difficult...
Rocket science is easy: take a tube, install pointed head on the other end and stuck some kind of engine on the other and you have a rocket! ....
 

BadDawg Bill

Well-Known Member
When you put on longer tubes you lift the front of the bike therefore changing the angle of the rake in relation to the center of the wheel.
So the longer the tubes (without changing the rake) the shorter the trail.

Different type bikes have different requirements but choppers need at least a 4" trail to be safe.
 

TapioK

Well-Known Member
When you put on longer tubes you lift the front of the bike therefore changing the angle of the rake in relation to the center of the wheel.
So the longer the tubes (without changing the rake) the shorter the trail.

Different type bikes have different requirements but choppers need at least a 4" trail to be safe.
Depending on on ofsett and rake on trees....
 

Jersey James

Jersey James
I installed 2 1/2" over stock Forks by Frank ("any bike, any length") on my 03 Pit Bull. Just wanted a different look. The bike rides rock steady at high speed. Although you really can't tell much difference in the appearance unless your parked next to another same year/model bike. I sometimes wished I had gone 4" over stock.
 

TapioK

Well-Known Member
The front will get lifted up no matter what if you don't change the rake....and that changes the angle of the rake in relation to the center of the wheel.
I remember some bikes have a negative rake on trees and even negative offset.. when my hangover is over And I can think, I figure how longer tubes effect on those... as mentioned a few times earlier rule of thumb is 4-6" trail. Though there are well behaving choppers with less and more ..
 

TapioK

Well-Known Member
I installed 2 1/2" over stock Forks by Frank ("any bike, any length") on my 03 Pit Bull. Just wanted a different look. The bike rides rock steady at high speed. Although you really can't tell much difference in the appearance unless your parked next to another same year/model bike. I sometimes wished I had gone 4" over stock.
Thats what most frame designers and builders say, you very seldom can notice 2" difference on ride.
 

Scooter33

Member
Thanks for the replies, some very good information on here. I was thinking someone on here had installed a set on their bike and had some pro /con feedback. I found the 2" over fork tubes on flea bay. I am going to hold off on making the purchase for now. In addition to the ground clearance / boot dragging issue, I have a high speed wobble. So far I have found the rear bearings are shot, installed a new rear tire, the rear disk and pads will be replaced, the front tire has uneven wear as well. I plan to replace the front wheel bearings when I get a new tire installed. After that I plan to make a high speed test again.
On a semi-unrelated topic, I was calling around about purchasing a rear tire with mount and balance to the local H D dealer. The service person first asked what kind of bike I had. He then said they could not help. So I pressed him as to why He said the wheel was too big for their equipment and the back would not need to be balanced. My first thought was BS and this chop just does not want to work on the Dog!
 

Th3InfamousI

Administrator
Staff member
Thanks for the replies, some very good information on here. I was thinking someone on here had installed a set on their bike and had some pro /con feedback. I found the 2" over fork tubes on flea bay. I am going to hold off on making the purchase for now. In addition to the ground clearance / boot dragging issue, I have a high speed wobble. So far I have found the rear bearings are shot, installed a new rear tire, the rear disk and pads will be replaced, the front tire has uneven wear as well. I plan to replace the front wheel bearings when I get a new tire installed. After that I plan to make a high speed test again.
On a semi-unrelated topic, I was calling around about purchasing a rear tire with mount and balance to the local H D dealer. The service person first asked what kind of bike I had. He then said they could not help. So I pressed him as to why He said the wheel was too big for their equipment and the back would not need to be balanced. My first thought was BS and this chop just does not want to work on the Dog!
The 300's most shops can't balance them as they really to are too big for the machine. Strokers can't even balance them and they are one of the top custom shops in the South West and a bdm dealer at one point. And most of us just use Dyna Beads and it removes the weights which are ugly

As far as mounting moat tire changers can handle a 300 but some may not want the liability or risk of damaging the rim. They make an extra arm to assist on these larger tires that a Harley shop may not have as they never see a tire over a 200 which is quite easy to change.

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