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Buffalo Bill
01-25-2016, 07:06 PM
Ok, so at my age, I don't think I'd let a lady friend ride on the back seat, just a fall over while getting off the bike might result in a broken knee, hip or back. Plus, I would never allow a rider without good safety gear.
So should I go ahead and mod my bike into a single seater for better handling?

Nessism
01-25-2016, 07:41 PM
How can removing a seat result in better handling?

jsandidge
01-25-2016, 07:45 PM
How can removing a seat result in better handling?

When it's attached to a passenger.

dorkburger
01-25-2016, 07:51 PM
The Kat / track bike I assume?

Rob S.
01-25-2016, 09:34 PM
I don't ride passengers but keep the back seat. It's where I bungee my knapsack when I do an overnighter. It then doubles as a backrest.

Buffalo Bill
01-25-2016, 10:14 PM
Ed, measure it's weight so you'll know.

Who Dat?
01-25-2016, 10:25 PM
I am with Nessism on this one. If the back seat hurts handling because it's attached to a passenger, the simple answer is "do not attach a passenger".

If you are removing the seat to save weight, you will have to balance how much of the seat you removed against how much your extra tail fairing will weigh. That is, unless you are using a Sawzall and just cutting off the back of the frame, too, as you won't be needing that, either.

Rob S.
01-25-2016, 10:28 PM
The Kat / track bike I assume?

Remind us of the bike model; maybe a pic.

Nessism
01-25-2016, 10:42 PM
Ed, measure it's weight so you'll know.

You are the one with the seat, not me. How about you measuring the weight and then posting up the info here? Also detail how you would go about "back seat gone".

Buffalo Bill
01-26-2016, 08:31 AM
Well, I'm looking for opinions about modifying classic bikes in general, the old moral frustration.
I never found a proper seat for my GS1100G, plus I've slowly been working on improving it's handling over the years.
There is a lot of steel, plastic and seat foam behind the riders butt that can go away. Specifically I'm considering cutting the 9" passenger seat out, and moving the tail section forward, plus a lightweight seat pan.
http://i619.photobucket.com/albums/tt277/BuffaloBill_1100G/Suzuki_GS1100G_82/12-15s_zps3znkztip.jpg

robertbarr
01-26-2016, 09:04 AM
Hmm. One of the nicest things about those bikes is the nice long, wide seat that allows the rider to scrunch around and change positions from time to time; even my cushy-looking Wing is lacking in that area. Of course, you're looking for a better handling machine, which is a different goal altogether.

I certainly wouldn't want to lose that advantage, but it's not my bike and it's not my behind...

Nessism
01-26-2016, 09:55 AM
That's a good looking bike Bill. It seems to fit you well also. No disrespect but I think you are crazy to think chopping up the backside of that thing will improve anything. I can't stand the way the so called cafe guys chop off the rear end of the bike. Looks like a stink bug with a miserably uncomfortable seat.

http://static-2.350cc.com/wp-content/uploads/2011/11/cafe-racer-.jpg

rudeman
01-26-2016, 10:56 AM
Improve the handling by cutting weight? You'll never even detect the benefit of paring the seat weight. In addition, you'll need to find a way to keep the dirt/water/mud off your back as it slings off the rear tire. Not to mention the overall unbalanced appearance of an abbreviated seat.

I would focus on something with more tangible benefits like raising the rear of the bike a little to quicken the steering. Maybe a fork brace to tighten up the front end a bit; made a noticeable difference on both of my GS1000's. Fresh/good tires would help too.

Tim Tom
01-26-2016, 11:05 AM
Don't waste the time cutting the seat / rear end off. It's a lovely bike you've got there. The weight savings is minimal, compared to the work involved.

What most certainly WILL improve the handling is getting some rear shocks on there that aren't completely sacked out. Perhaps some that are slightly longer than stock to quicken up the geometry. I had 14" Ikons on my 850G and they transformed the way the bike steered. Some fork springs and heavier fork oil also help out a lot. And then to match your new found nimble-ness, throw on stainless steel brake lines. All of a sudden your GS will brake and handle much better than it used to.

storm 64
01-26-2016, 11:06 AM
Not to mention the crime of cutting up a perfectly good seat and tail section...

tkent02
01-26-2016, 11:34 AM
You want a better handling bike get something a hundred pounds or so lighter, shorter and designed to handle better. An 1100G is not going to be quick and nimble no matter what you cut off.

JJ
01-26-2016, 01:29 PM
You want a better handling bike get something a hundred pounds or so lighter, shorter and designed to handle better. An 1100G is not going to be quick and nimble no matter what you cut off.

Yeah, what Tom said!! ^^^

Buffalo Bill
01-26-2016, 05:58 PM
I've had and said all those opinions myself a few times, and posted them here.
I'm not looking to do some artsy, or fugly bobber job, just bring the OEM tailpiece forward 9", and maybe a GSXR seat. Keep the OEM look and paint job.
I'm gonna raise the fork tubes enough to use clip-on bars, and that will likewise lower the front end.
As for what it is now, the seat is too long, over padded, crude and heavy.
I do feel bad about cutting the frame, but you can hardly sell these bikes nowadays, old riders are getting fewer in number everyday.

Tim Tom
01-26-2016, 06:06 PM
You could get an Airtech endurance racing style rear end. You'd need to modify the rear subframe to get it to fit, as well as create a new riders seat. If done correctly it can look pretty good. Depending on the seat pan, you may not have to trim that much off the subframe.

At the end of the day it's your bike, do with it as you see fit.

dorkburger
01-26-2016, 09:25 PM
43943

This is a fine looking G bike. (Love this pic BTW). Personally I would leave it. Plus, as Rob S said earlier, the back seat is a god spot for saddlebags, etc, unless you don't have a need.

tkent02
01-26-2016, 09:43 PM
43943

(Love this pic BTW).

Me too, been there on bikes with Dave. Nice place.

Buffalo Bill
01-26-2016, 11:53 PM
Thanks. I don't want to fk-up that look at all.

Chuck78
01-27-2016, 09:46 PM
You want a better handling bike get something a hundred pounds or so lighter, shorter and designed to handle better. An 1100G is not going to be quick and nimble no matter what you cut off.

What he said...if it has a G in it and its not a gs650g, then it's probably not going to ever be the best handler candidate. it will handle pretty well with the right work, but the seat would be at the very tail end of the handling improvements checklist!

Get a GS1100E or GS1000, chain drives...Install GS1150 rear wheel and/or identical looking 1st gen GSXR 18" wheels (3.50 or 4.00x18 rear, 2.75x18 front, runs tubeless radials!). 86 gixxer I believe even still used a 15mm axle if you are modding GS forks with emulators and anti-dive deletes. Get some good gripping rubber. Swap a Bandit GSF1200 fork & calipers in custom wider $325 Weiss Racing billet triples with careful rake&trail triple clamp offset calculations, & width enough to clear the wheel spokes away from the massive opposed piston calipers. Or buy a VTR1000F Superhawk 41mm adjustable dampening cartridge fork and Race Tech cartridges for it, & Honda PC800 triples (plenty of offset to make for easy steering w/18" (& even 19"!) front tire without needing extreme rake steepening ) [CBR600F2/F3 forks & 2piston sliding calipers also are great but not as huge of braking upgrade but still drastic upgrade, 2 piston sliders clear our old wheels better with narrower triples like the 41mm CB750 NIGHTHAWK 90's 41mm model's192mm width, fits the cbr/vtr forks, looks to be close on the steering stem, if not a 1984 VF1000F interceptor triple may have a better stem length], $499 YSS Z-362 TRL adjustable dampening aluminum body 36 mm piston shocks (http://www.yssusa.com/series-z.html) in a length longer than the 320mm stockers (&test out their +10mm ride height adjuster for further rake steepening & trail reduction, steepen rake w/shock length until you get to 3.95" or 3.8" trail - very critical to reduce the trail from stock but not much below 3.8 inches or 95mm).
THEN...try that Airtech streamlining look rear end and a small nose fairing Mad Max (the original 1st movie of the series) style or Rickman half fairing. Superbike bars. No rear sets.
THAT would be my opinion on improving your motorcycle handling! And Keith Code book reading & movie watching ("A.Twist.of.the.Wrist.ii" on youtube)

Of course you can do all of those things to the GS 1100 G! aside from the rear wheel swap, you are permanently stuck with the shafty rear wheel. Longer ($300-$500++) shocks and dropping to an 18 inch front wheel if you don't have one already will be a big steering improvement. Much more noticeable than losing a few pounds behind your rear end. Avon AM26/Pirelli Sport Demon/Shinko 230/Battlax BT45 tires in the stock sizes for your bike or better the size recommended for your rim width by the tire manufacturer, everyone except Pirelli publicizes of their specs readily. I use the others as a cheat sheet for Pirelli consideration, fairly universal size vs rim fitment. Do just those mods and Race Tech cartridge emulators with race tech or sonic springs, and you will have drastically improved your bike's handling.

Chuck78
01-27-2016, 09:47 PM
You could get an Airtech endurance racing style rear end. You'd need to modify the rear subframe to get it to fit, as well as create a new riders seat. If done correctly it can look pretty good.

At the end of the day it's your bike, do with it as you see fit.

Yeah, what he said... your bike, do what pleases you, I just cringe when people make permanent alterations. As in chopping the frame a lot without improving the frame in other areas such as the popular "OSS" Old Skool Suzuki frame bracing layout.

that Airtech look could be pretty slick looking. I would upgrade the suspension drastically before doing anything else though. you can save part of the weight of your seat and tail section by putting on high end aluminum shocks versus steel stockers!

honestly, I keep the dual seat on my GS750-920cc for the odd event that I may require a passenger, such as when a buddy (likely on a harley or dohc 79-82 CB!) breaks down, or random situations, and because it is really convenient to throw my saddlebags on and then even strap a backpack on top of that. And as also mentioned, it is nice to be able to slide further back on occasion, I often lay on my tank and slide real far back on the seat on long highway rides.
I don't know what I will do with this solo seat Rickman CR900 that I am resto-mod resurrecting with a GS750-894cc engine. make a custom clamp on luggage rack to go over the fiberglass racer tail section? with the incredibly long gas tank of the Rickman solo seat version, even with 1" riser clip ons, I probably won't be wanting to ride it even 3.5 hours (i.e. probably 5 or 6 hours the "scenic i.e. TWISTY" route) to the Red River Gorge in Kentucky for the dotheton.com spring thaw event.

Buffalo Bill
01-27-2016, 10:20 PM
Chuck you just don't have a short comment on anything technical! ;)
As for trimming down the weight on any production bike; well it's a process of eliminating many small things that add up together.
This seat change may eliminate 10 lb, plus it's a performance upgrade most people overlook; putting your particular body in the ideal position for track riding.
I upgraded the shocks and springs last summer. As for getting 17" wheels in there, nah, wanna stay OEM, production stock.
Might try a brake disc upgrade later.
I could probably still bolt on my luggage rack after this mod, but I rarely do any long distance riding.
As for why do this to a 1100G?, because that's the bike I own.

Chuck78
01-27-2016, 11:46 PM
Chuck you just don't have a short comment on anything technical! ;)
I know...I know... I'm always on a quest to learn everything I can about vintage bike modifications and maintenance.


This seat change may eliminate 10 lbs
Bonus! just make sure the seat padding is more comfortable than stock!



As for getting 17" wheels in there, nah, wanna stay OEM, production stock.
Might try a brake disc upgrade later.

1st gen GSXR 18" wheels (look identical to the later GS mags)
Oh wait, I forgot, shafty... stuck with the back wheel at least. If you have a 19 inch front, get rid of it and get an identical looking 18 inch front. this will help the steering response drastically.

Drop the triples a slight bit on the forks, this will substantially quicken the steering and make it feel very much more sporty, getting the rake and trail closer to modern specs.
Racetech gold valves in those forks is ESSENTIAL. Tarozzi fork brace is a very nice compliment if you are running it hard.

other than that, looks like lightening up the bike is definitely the direction you need to go if that is your goal to improve it further. VM33 smoothbores & k&n's will probably help you lose more weight than the seat project versus the stock carbs and air box, and will be another performance bonus. and a good four into one while you are at it.that is a drastic weight savings just to swap the exhaust. Then center stand, charging system upgrade and lithium iron phosphate battery. lightweight plastic LED turn signals. Plastic headlight bucket. Smaller gauges....

the salty monk twin pot brake mod is another big weight savings, drastic on the unsprung weight savings, and drastic improvement in stopping power! I cannot recommend this enough!

Chuck78
01-27-2016, 11:50 PM
I dropped 50 pounds off of my bike without doing anything terribly exotic, and it still has the stock 77 flat dual seat and GS tail section, & very slightly lighter CB 400 turn signals. Very minimal custom machined parts, only for my version of the twinpot brake mod

Rob S.
01-28-2016, 12:14 AM
...This seat change may eliminate 10 lb...

Just the seat, not counting the frame (ouch!) cut? You think that much?

Buffalo Bill
01-28-2016, 08:26 AM
Chuck you mentioned "charging system upgrade", does this eliminate the honking big stater sticking out of the left side?
That is a huge problem with the big GS bikes, the damn thing touches down if you try a deep lean left turn.
PS: I just purchased a seat from an 89 GSXR750, have to have it in hand just for a test fit.
http://i619.photobucket.com/albums/tt277/BuffaloBill_1100G/Suzuki_GS1100G_82/s-l1600top_zpsuchmcbn7.jpg

http://i619.photobucket.com/albums/tt277/BuffaloBill_1100G/Suzuki_GS1100G_82/s-l1600_zpstcnaouhv.jpg

limeex2
02-03-2016, 02:27 AM
Leave it. If you want light weight your starting on the wrong bike. Even though you mention you cant give 'em away, that's a really nice, clean one. Get rid of exhaust 15 lbs. + 5-7hp. Switch to 33 flat slides save 4 lbs + 5-7 hp degree cams. new longer shocks. Salty monk brakes.Get dynoed. It will change the drivability and personality of the bike like you would not believe. For passengers, get a Gold Wing, I may have to,she just didn't understand...

Tim Tom
02-03-2016, 10:58 AM
Chuck you mentioned "charging system upgrade", does this eliminate the honking big stater sticking out of the left side?
That is a huge problem with the big GS bikes, the damn thing touches down if you try a deep lean left turn.
PS: I just purchased a seat from an 89 GSXR750, have to have it in hand just for a test fit.

If you are scraping the engine cases, you DEFINITELY need to install some longer shocks. The added ground clearance will solve that. Also you should try moving your body weight to the inside of the turn, the more you hang off, the less lean angle you need to get around a corner at a given speed.

As far as I know the only way to remove the stator, is to convert the bike to run a total loss electrical system. Other than racing, it is not practical to do this.

tkent02
02-03-2016, 11:30 AM
Chuck you mentioned "charging system upgrade", does this eliminate the honking big stater sticking out of the left side?
That is a huge problem with the big GS bikes, the damn thing touches down if you try a deep lean left turn.


And you lowered the frame by raising the forks anyway?

rudeman
02-03-2016, 12:44 PM
...I upgraded the shocks and springs last summer. As for getting 17" wheels in there, nah, wanna stay OEM, production stock.
Might try a brake disc upgrade later...

You upgraded the shocks last year? There's some serious sag there. Those shocks look as if they're about to bottom out just sitting there.


...I could probably still bolt on my luggage rack after this mod, but I rarely do any long distance riding.
As for why do this to a 1100G?, because that's the bike I own.

Are you serious about this endeavor?

Buffalo Bill
02-03-2016, 12:48 PM
Ain't never gonna find a place to lean a bike that far on public roads, will not be riding it on a track.
Looks like the foot peg will touch down an inch before the case too.

tkent02
02-03-2016, 12:50 PM
Footpegs fold, but if you're scraping them you're not doing it right.

Tim Tom
02-04-2016, 10:36 AM
You upgraded the shocks last year? There's some serious sag there. Those shocks look as if they're about to bottom out just sitting there.

Agreed! They look at least an inch and a half shorter than stock, whether that's from sag, or just a short spring, I can't say. But they are on the short side of things.

Buffalo Bill
02-04-2016, 11:35 AM
They do look kinda lowish, but those are exactly the same length as the OEM I took off; 320mm.

Tim Tom
02-04-2016, 11:41 AM
They do look kinda lowish, but those are exactly the same length as the OEM I took off; 320mm.

Did you measure the old ones, and used that as an indication of how long they should be? It's quite possible the old ones were sacked out and shorter than when they were new. I believe the OEM size was 330mm, but I could be wrong.

How much do they compress when you sit on the bike?

Buffalo Bill
02-04-2016, 03:01 PM
Ok, I took a bread knife to the seat, seems the foam was 4" thick, plus another inch deeper in the center.
Sliced off a good 2.5", and made new seat cover. This will do for now.
http://i619.photobucket.com/albums/tt277/BuffaloBill_1100G/Suzuki_GS1100G_82/new%20cut-4s_zpsqqhaqjhn.jpg

rudeman
02-04-2016, 03:14 PM
You should be aware that the aft side of the tank will be vulnerable to scratching from zippers or even belt buckles especially under hard braking. You can put some clear plastic sheeting on that area to protect it.

Those shocks look way short to me. The Ikon site specifies 12.99" shocks for the 1100G. In millimeters that's 329.946mm or 330mm. If you have 320mm units they're a little short; roughly 1/2". NBD but it does make for a slightly slower steering bike, not to mention the loss of some cornering clearance. maybe fit a pair of 95/140 springs as well.

Seat looks good. You may want to replace the OEM foam with some higher density foam to keep your backside and family jewels from feeling the seat pan.

Tim Tom
02-04-2016, 06:59 PM
I like the looks of that scooped out seat! Looks much sportier. Good stuff.

Buffalo Bill
02-04-2016, 07:43 PM
I bought these shock extenders from Hong Kong.
For less than $8, no problem giving them a try.
http://i619.photobucket.com/albums/tt277/BuffaloBill_1100G/Suzuki_GS1100G_82/s-l1600_zpsxfmikyi1.jpg

Tim Tom
02-05-2016, 03:04 PM
For $8 they are worth at least a bolt on and bounce test... Please paint them black though!

cwaugh16
02-07-2016, 12:49 PM
It looks great. Not only cutting down the front for "sport" look but leveling out the rear so that it flows smoothly to the tail section. The suggestions on suspension and brake upgrades earlier are the way to go. You should resell the GSXR seat back to ebay.

kaufen
02-10-2016, 06:53 AM
Don't hesitate to modify to single seat