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Old 02-22-2012, 11:27 AM   #1
SPO OP
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R80ST fork swap wisdom needed

So, I'm enjoying daydreaming about what my ST will become. I'm just not sure what that actually is. As a few of you may know, I'm riding the CDT this August. I'm not saying I bought this bike specifically for this ride, but I'd be lying if I said I haven't romanticized (ala Motorcycle Diaries) about bombing wide open fire roads on this classic airhead.
All that being said, I've read the various fork swap/upgrade threads and I'm left feeling like I don't know which way to go. I'd like to improve the front end of the ST, but I'm not sure all the trouble/cost of a non GS front end would be worth it for me.
My ST is my only bike, and will serve many purposes. City bike, fire road explorer, long distance traveller. I know that people say to just leave the bike as is, and buy a KTM/KLR/blah blah for the off road stuff. Truth is, I'm not in any hurry to get ANYWHERE and don't plan on racing. In addition, if people are that concerned with keeping an ST stock, they should buy one for themselves.
So-I'd like to upgrade the front end for the occasional dirt dalliance, make it nice and stiff for twisty bumpy paved roads (I do live in Oakland, after all), keep the ride height as close to stock as possible, and not break the bank with a swap.

GS front end slid up into the triples, with upgraded inserts? WP super Gucci? KYB?

How did you guys decide on what forks to use?


Dang, I feel like I need a flow chart!
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Old 02-22-2012, 12:39 PM   #2
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I went with a G/S front end. Mostly to get a 21" front wheel for very similar reasons that you described. It caused a domino effect of parts swapping that is much more involved than I initially thought.

I ended up changing:

Front end parts:
forks
21" wheel
fork brace
axel
brake caliper (G/S and ST calipers are not the same)
Fork gaitors
Acerbis front fender

Chassis:
G/S center stand
rear shock
G/S style (Tomasalli) handlebars
G/S oil sump, shallow oil pick up, shorter oil dip stick

Because I wanted to fit a bash plate I had to go with a G/S sump with mounting points for the plate which involved getting a shallow oil pick-up and shorter oil dipstick

And of course a bigger tank. I went with a R100GS 24L tank that gives me a touring range of just over 400 kms

From:


to:


to:
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Old 02-22-2012, 12:58 PM   #3
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Quote:
Originally Posted by scarygary View Post
I went with a G/S front end. Mostly to get a 21" front wheel for very similar reasons that you described. It caused a domino effect of parts swapping that is much more involved than I initially thought.

I ended up changing:

Front end parts:
forks
21" wheel
fork brace
axel
brake caliper (G/S and ST calipers are not the same)
Fork gaitors
Acerbis front fender

Chassis:
G/S center stand
rear shock
G/S style (Tomasalli) handlebars
G/S oil sump, shallow oil pick up, shorter oil dip stick

Because I wanted to fit a bash plate I had to go with a G/S sump with mounting points for the plate which involved getting a shallow oil pick-up and shorter oil dipstick

And of course a bigger tank. I went with a R100GS 24L tank that gives me a touring range of just over 400 kms

From:


to:


to:
I'm pretty sure our bikes are gonna end up being twins. It's a slippery slope. I've got the GS tank ready to install (second petcock is needed and then it just feeds the right side carb only? As in one petcock per carb? Link up the fuel lines?).

How do you like the way your bike handles since the fork swap? I'm thinking that I'll get an aftermarket ST length rear shock and slide the fork tubes up into the triples a little to try to stay near the stock geometry/height. Is that crazy?


Thanks Gary! Sharp looking ride you got there. Though, I must say-the pic of your bike pre-GSification with just knobbies pushed me over the edge, purchase wise. Too damn sexy.
It 'seems' like the GS front end is the most economical way to go...
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Old 02-22-2012, 01:26 PM   #4
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Quote:
Originally Posted by SPO View Post
I'm pretty sure our bikes are gonna end up being twins. It's a slippery slope. I've got the GS tank ready to install (second petcock is needed and then it just feeds the right side carb only? As in one petcock per carb? Link up the fuel lines?).

How do you like the way your bike handles since the fork swap? I'm thinking that I'll get an aftermarket ST length rear shock and slide the fork tubes up into the triples a little to try to stay near the stock geometry/height. Is that crazy?


Thanks Gary! Sharp looking ride you got there. Though, I must say-the pic of your bike pre-GSification with just knobbies pushed me over the edge, purchase wise. Too damn sexy.
It 'seems' like the GS front end is the most economical way to go...

The bike handles pretty good the way it is set up. This is no sport bike but it can provide plenty of entertainment on the twisties.

I don't mind the added height of the G/S set-up and I bet I am shorter than you :) The bike is so well balanced that you never get that top heavy feeling from more leggy modern bikes. If you are going to look to the aftermarket for a shock and want to stay in the ST length I think your options are limited.

If you go with the G/S front end, you will gain only 1" or 1.5" of ride height. I can't answer to the GS front end but I imagine you would gain another .5 - .75 inches over the G/S front end. BTW there is no "sliding the forks up" on the G/S or ST front end. The fork cap nuts sandwich the triple top plate with the fork tubes making for a non adjustable ride height.

I did like the stock look of the ST with knobilies.. I have all the ST bits in boxes to put it back if I want to... but right now I like the bike so much better the way it is and the way it is evolving.. It's not done yet.
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Old 02-22-2012, 02:00 PM   #5
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For my ST I went with R100GS forks (among other things). If I weren't building this bike into an HPN, I'd keep it exactly the same. The R100GS front end worked out great. I didn't change my centerstand either. I'd also put some thought into a heavier duty rear shock. The stock ST shock is not up to load carrying on unpaved roads. I bent mine in half. I'd say that GS forks are in a completely different league than G/S forks. Much stiffer (and heavier too probably), tubeless front wheel, better brake, GIANT axle, real triple clamps, and also much more easily available.


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Old 02-22-2012, 02:02 PM   #6
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Quote:
Originally Posted by scarygary View Post
If you go with the G/S front end, you will gain only 1" or 1.5" of ride height. I can't answer to the GS front end but I imagine you would gain another .5 - .75 inches over the G/S front end. BTW there is no "sliding the forks up" on the G/S or ST front end. The fork cap nuts sandwich the triple top plate with the fork tubes making for a non adjustable ride height.
You can slide GS forks up no prob.
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Old 02-22-2012, 03:04 PM   #7
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There is no way I'd put G/S forks on an ST....just a waste of money and no upgrade. The G/S fork is is a piece of noodley shit!!!!

For moderate use the R100GS fork is up to the task and a huge improvement in ride and tracking. Bad thing is finding one, you'll want the complete front end assembly, brakes, wheel, triples, turn signals. You don't need the handle bars or master cylinder, but will want the metal caliper line. I'd advise finding a pre 1990, due to being able to use turn signal brackets. The 1990 on wards is easier to adjust the headset bearings.

Now for the bad news, good luck finding the front end. I found my set in Germany (Ebay), bought the complete assembly and the front rim was warped. Oh well gave me a reason to get rid of the tubeless rim. Expect to drop at least $800 if your lucky, more likely $1,100.

A DR 650 front fits relatively easy, but you may not like the bastardization of your BMW.

With either front you'll probably want to change to a G/S rear shock for longer travel.
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Old 02-22-2012, 04:26 PM   #8
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Quote:
Originally Posted by One Less Harley View Post
There is no way I'd put G/S forks on an ST....just a waste of money and no upgrade. The G/S fork is is a piece of noodley shit!!!!
the damage is done.. I guess I'll have to live with it
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Old 02-22-2012, 04:29 PM   #9
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Oh geeze, Seth. You just started the new "oil" thread among ST and G/S riders.

I've been through 3 front ends.

Stock with race tech gold valves and homemade fork brace. Rear, Wilbers 642 shock.

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I loved the ST front end on the street, but hated it off road. I bent fork tubes often, the brake sucked, and it was a noodle off road.

Take 2. The DR650 front end with Intimidators and .55kg springs with fork brace. Sent the Wilbers back and had a G/S length shaft installed.

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It was affordable, and much better. I felt more planted off road, I rarely bottomed the front out with the stiff springs, but I really missed the turning radius of the stock front end. It was difficult to turn the bike around at the end of trail that pettered out. I'd at times have to flop it on the head and spin it. The bike turned in much quicker also, but I got used to that. It was just moving it around in tight spaces was much more difficult. I liked the DR front end and still have it, but I wanted more. I want to race the bike, but like you it is my touring bike, my fun bike, and I use it at work. I teach on this bike. So my comprimise was stock steering, and bad ass forks!!!

So take 3. Custom triples by Rdubb, crafted by HPNguy. WP 5060 forks.

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The one thing I wouldn't do, unless you get it for free, is put the G/S forks and triple on. It just isn't worth it. You'll get a 21" wheel out of the deal and that's it. If you want cheap but noticable difference, go with a DR front end. Got money to burn and feeling lucky? GS forks and tubless wheel!! There are other forks that you can modify to work on your bike, CR250 usd forks will fit as will a YZ 450f forks, I can't tell you what years for sure, but wouldn't be hard to figure out.

I feel like you may be getting ahead of yourself. I didn't change my forks until I had owned the bike almost 5 years. And I did a lot of "no-no" stuff with the stock front end. And I survived! Get to know the bike before you make any descisons. Unless a GS front end falls in your lap, leave it stock for a while and just ride the piss out of it.!!! I love my ST!
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Old 02-22-2012, 04:38 PM   #10
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Quote:
Originally Posted by scarygary View Post
the damage is done.. I guess I'll have to live with it
sorry to be so harsh, but I hate the G/S forks...you'll find out why..... just hope you don't have the same experience w/ them that I did. Tank slapper into a guard rail. Be very careful with the fork induced wobble, gets worse with loads on the rear, higher speeds and bumps in mid curve. Trust me they are down right dangerous, not bad w/o bags and gear. I thought I was riding below the wobble conditions and knew in the back of my mind that the wobble was an issue and "might" rear it's ugly head if certain conditions arose. In my case it was camp gear on the back, a mild sweeper at 50 mph and a rough bumpy center line all those conditions at once caused a violent tank slapper which ended partially under a guard rail. One mildly bent fork, busted windshield, mirror and turn signal. No broken bones, bruised thigh and arm....I was lucky as no cars were approaching. Pulled the bike out from the guard rail and continued on to the Georgia Mountain Rally via some good mountain 'roads", With a slightly bloody t-shirt I limped to the ranks of those motorcyclists that have crashed. I carry the badge of honor on my right bicep.
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Old 02-22-2012, 04:44 PM   #11
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A while ago I bought a complete R100GS front end off IMBWR for about $1k.
Looking forward to making the transition but am waiting till I have a G/S length rear shock in hand.

I ride some unimproved roads but the jarring can get excessive and the front wheel feels a little inclined to wash out.
I haven't ridden more dirt-capable bikes to make an informed comparison.

I gather the relative sturdiness & travel of the GS forks will help with the former and the 21" wheel the latter.
It will also broaden the tire options considerably.

It's gotten to the point that whenever I get out in the dirt I swear the next time will be with the GS front end.



30" inseam. An R100GS is a bit tall but manageable.
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Old 02-22-2012, 04:44 PM   #12
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Quote:
Originally Posted by hardwaregrrl View Post
Oh geeze, Seth. You just started the new "oil" thread among ST and G/S riders.
I've been through 3 front ends.
I love my ST!
The options and combinations are seemingly endless. Modding is a slippery slope.. but it sure is fun..

I love mine too. It's hibernating at the moment.
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Old 02-22-2012, 04:57 PM   #13
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Renner- best mod you can do to the bike!!! hope you got every thing. Do the four pot caliper mod too!!!! Scan through my link below for some tid bits about the GS front. Your stock springs will be weak. I've got some uprated springs ( setup for HPN tank) and gold valve which will be for sale when the insert buy goes through.

I wouldn't even think of letting someone ride my G/S with the stock forks due to safety concerns.
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Old 02-22-2012, 05:14 PM   #14
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There is no way I'd put G/S forks on an ST....just a waste of money and no upgrade. The G/S fork is is a piece of noodley shit!!!!
I gotta agree with him. Also, I think you'll pay more for a G/S front end, if you can find one, than a better modern fork. I'm not a fan of the GS front end either--again it's expensive and still not better than many other modern forks. The main reason I swapped front ends wasn't for suspension, I'm not so good of a rider that I think I need world class suspension, it was for brakes. The stock brakes are really bad and extremely expensive to upgrade. You can get a whole new front end for what you pay for a 320mm rotor and new caliper for the stock fork.

The DR fork is not the pinnacle of technology but they're inexpensive and they bolt up with no modification. What Jenna mentioned, the steering lock, is the only downside. When you're riding the bike the lower offset will give you more stability so I'd say it's a good thing. The problem comes in when the trail disappears and you need to do that 3 point turn to get out or you're trying to maneuver it around a cramped garage. The swap shouldn't take more than a few hours. Also, the DR forks are height adjustable. You can cut a few spacers to lower them meaning you wouldn't have to raise the rear end by getting a new shock.

I want a set of WP 4860 upside down forks myself. Now that I know more, I'm more willing to deal with getting the stem machined or getting a set of custom triple clamps. The thread that AW put together makes it a more accessible build also. I'm going to get a few more years out of my DR forks first though.



Jenna destroyed her ST front end riding offroad. She bent one tube and metal shavings came out with the fork oil--that was after getting a new top triple clamp, a fork brace and gold valves. That being said, Jenna rides the piss out of that bike. She hits jumps with a 12 gallon tank and boxes. We mere mortals are not so hardcore If you just want to go down a mild dirt road I think you'd be fine sticking with the ST front end.
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Old 02-23-2012, 05:16 AM   #15
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