35MM vs. 39MM front end

[75gn]

Will I notice a difference by 'upgrading' to a 39MM front end on my '78 FX? Input is appreciated...

[Racepres]

On an FXR Yes...On a 4-speed?? Probably not much...
I would Not waste the $$ unless I got it cheaper than stock and needed it....

[govmule84]

I think it's worth it if nothing else because you can go dual-disc at that point, and then slam some cartridge emulators or cartridge kits in there.

That alone would make it worth it for me if I had to have a front end that was a good performer.

[Racepres]

I have more than one dual disk 35mm F.E.
And am willing to bet that blindfolded you could Not tell the difference on a 4-speed chassis...Course...Blindfolded yer gonna skin yer ass anyway!!!!

[Dr. Benway]

Originally Posted by govmule84

I think it's worth it if nothing else because you can go dual-disc at that point, and then slam some cartridge emulators or cartridge kits in there.

That alone would make it worth it for me if I had to have a front end that was a good performer.

I love 39mm front ends. To me they feel better, can be built up as Mule mentioned. The overall quality seems higher, and as far as aesthetics go I prefer the nice matching aluminum top and bottom trees. You can also cheat the tubes up or down a little in the trees if you need to.

[ralphiejantz]

Originally Posted by Dr. Benway

I love 39mm front ends. To me they feel better, can be built up as Mule mentioned. The overall quality seems higher, and as far as aesthetics go I prefer the nice matching aluminum top and bottom trees. You can also cheat the tubes up or down a little in the trees if you need to.

Yeah they are definitely a better feeling and handling front end, no question about that, plus they can be modified to have a little better performance.

As far as not being worth it on a 4speed frame
if you like the look and the better braking performance they will give you than they absolutely are worth it on whatever bike you want to put it on.
The 35mm front ends are very sloppy feeling (even when rebuilt)
the 39mm does feel a little bit tighter etc.

So if you like the way they look and are looking for a relatively cheap upgrade go for it

[twistedtee]

No doubt you'll notice a difference.

[lilbill]

i like the way they look. this one is off a 1200r sportster.

[Blackbetty]

39mm's are cleeeeeaaannn




These are dropped 2" using Ness damper rods

[Racepres]

Originally Posted by Blackbetty

39mm's are cleeeeeaaannn




These are dropped 2" using Ness damper rods

Cheap too ...Huh?
Tax and Spend Boys......

[Dr. Benway]

If you don't like them, don't use 'em.
Leaves more for the guys who appreciate them.

[Racepres]

Originally Posted by 75gn

Will I notice a difference by 'upgrading' to a 39MM front end on my '78 FX? Input is appreciated...

Yea....You'll notice a Huge Difference...If ya don't...Well you shoulda!

[Coco]

I went with 39mm over 35mm for aesthetics with the cleaner look and the alloy top and bottom trees like others have. Mine were off an FXR I think. I got mine dirt cheap at $250 with shaved sliders so I grabbed them. Seems to be plenty of performance upgrades for them too. All I did to mine was lower them 2" , use progressive springs and put in some pre-load adjusters.

[Mike Britton]

How well would a 39mm work on a Triumph? I really like the front end in post # 10.

[Dr. Benway]

Originally Posted by Mike Britton

How well would a 39mm work on a Triumph? I really like the front end in post # 10.

Very well. I had one on my '67. I had to make adapters to get the bearing races to fit, but I think they have kits now.

[Coco]

Originally Posted by Dr. Benway

Very well. I had one on my '67. I had to make adapters to get the bearing races to fit, but I think they have kits now.

I have the 39mm narrow glide on my Triumph. You can get bearing retro fit kits from Lowbrow with a Timken style bearing. They fit nice with no issues.

[FRISCO67]

This might be an option but I know you get Progressive Suspension springs for a 35mm and apparently you cam get emulators for 35mm forks also.
But saying that they would probably only end up being about as good as a 39mm set, but then again it would be about same price as buying a set of 39mm.

http://racetech.com/page/title/H-D%2...mulator%20Kits

[KCgran]

Originally Posted by lilbill

i like the way they look. this one is off a 1200r sportster.

Ooooo.... The coffee table bike!!!! I love this bike. Did you ever get it done bill?

[Truckedup]

Originally Posted by Mike Britton

How well would a 39mm work on a Triumph? I really like the front end in post # 10.

I installed a 39mm Sporty fork assembly on a Triumph using a bearing conversion kit from a local custom bike shop. Personally I think it looks too bulky on a Triumph, like a slim woman with fat legs...

I believe what Racepres is saying is that a 4 speed frame is too flexible and most bikes will run out of ground clearance to benefit from the 39mm forks in regards to handling.

[Racepres]

Originally Posted by Truckedup

I installed a 39mm Sporty fork assembly on a Triumph using a bearing conversion kit from a local custom bike shop. Personally I think it looks too bulky on a Triumph, like a slim woman with fat legs...

I believe what Racepres is saying is that a 4 speed frame is too flexible and most bikes will run out of ground clearance to benefit from the 39mm forks in regards to handling.

I'll go beyond that and say my buddy owns a '94 FXR, mine is a Shovel FXR....I have not witnessed any real difference....But, In defense of the 39, I have incorporated a "tweek" bar...Long ago. It is Doubtful his would benefit from one.
But, Yea...A 4-Speed???? C'Mon guys! I'm sure lots of you have Honest Hot Rod 4-Speed Big twins But, In the Real World. That ain't no Race Bike!!!!!
Before ya get all Puffed-up, Get a Time Slip or I'm Not Impressed!!!!!
Cause on the Dyno...I don't think ya even Need a Front end!!!!!