New '81 GS750L

[Hoosier]

Hello everyone,
I just picked up a 1981 GS750L, 17,500m, as my first road bike actually! I grew up on dirt bikes (YZ 250f) so I know how to handle them decently well. It runs well (from what I can tell). Ive already replaced the oil and front brake fluid, however the front brake calipers tend to stick so I may need to replace those. I notice the ride was really soft, or at least didn't feel right and it turns out the rear suspension was blown, so I've ordered some after-market 13' suspension that I hope will be an easy install (can I just put it on its center stand?) I want to paint them silver like the original shocks so they match the bike but Im not sure if Im going to. All in all the bike is great, its much more powerful than I anticipated which is a nice surprise, Ive got loads of complements on it and its all stock expect the turn signals. It even has the original seat with zero rips which Im told is rare! Please let me know if there is anything particular with the 81' or "L" model I should be looking for.

Cheers,
- S

[Guest]

Sounds like the calipers need to be dismantled, cleaned and new boots installed. While you are at it I would swap out the rubber lines with stainless braided ones. As for the rear shocks I went the extra mile and installed gas ones on mine. They were not available in the day, but sure make for a more comfortable ride. Check out Progressive or Sonic shocks and springs. My seat looked fine a few years ago but is now cracking as the foam has deteriorated over the years. They are available at Pitreplica. Original design. Keep this in mind for the future. As for the rest, check out Basscliff's website. There is a list of things to look into to keep your bike running in top shape for many years to come. Sounds like you picked up a really good bike with low mileage. Best of luck with it and welcome to the funny farm. Oh.... and yes, we love pictures.

[Jedz123]

The 81 750L was my first motorcycle. Put over 50k miles on it, I got mine in 2007 so it was pushing 30 years old and needed work for it was $500 bike, First thing to do is upgrade to twin stoppers in the front. I installed progressive springs and 1000E rear shocks. That took away allot of slop. Also brand new tires are a must if handling is what your looking for, Should look for a 530 chain conversion down the roads. My bike responded very well to pods and opened up exhaust. Very quick.

The L is the Harley knock off... Loads of chrome and slushier suspension. Easy fixes. Great bike but I eventually got a newer bike for I demanded some big miles.

Issues Ive had were these: Stators (went through 2), R&R (Just grab a modern 3 leg R&R of a FI GSXR and be done with it), batteries, rear tires would only last 2k miles, overheats easily in hot conditions, lastly the engine seals all started to go at the same time leading to excessive oil leaking. I ended up doing a 7-11 swap and that was done.

I wish I had a 750L but they are hard and few to come by now. Great bikes.
Enjoy! Please post some pics too!!!

[Hoosier]

Thank you for the quick replies. I'm a freshman in college so my available funds are limited at best. I will try to make all the upgrades/ refurbishes that you guys recommend but I wont be able to do them all. Since I have limited funds, I want to be able to the most for my bike with the least amount of cash possible. If there were a list of top 3 or 5 things I should spend money on that would give me the most bang for my buck, what would they be? I already replaced the spark plugs with some very nice ones and that seemed to help a ton.

[Hoosier]

Here is the link to the album with some pictures. http://www.thegsresources.com/_forum...p?albumid=3195

[Hoosier]

Also, I am new to heavy maintenance on a motorcycle so I am unsure of what a lot of this terminology is. Progressive springs? Twin stoppers? 530 chain conversion? pods? opened up exhaust? (Ive heard mention of this once, that taking out the "inner parts" of the exhaust on this bike will make it sound better/louder) R&R? 7-11 swap?

Sorry for my gross inexperience. I'm sure that if I dug into Basscliff's website I would be able to figure some of this out but I have no idea where to start.

Cheers

[Guest]

Progressive springs are a front suspension upgrade that will improve the handling.

Twin stoppers. Your bike has one disc on the front - it's not that difficult to install a second disc/caliper, leading to greatly improved braking.

530 chain conversion gives you lighter chain and sprockets. Not sure if you get a better choice of modern chains.

Pods replace the standard air filter on the bike.

Opened-up exhaust. You've already worked that one out.

R/R = combined regulator and rectifier. A weak spot on the electrical system of old Suzukis.

7/11 swap = replacing the 750 engine with one from an 1100 cc machine.

Probably the best place to start is Basscliff's site, along with checking the electrical system - find any post from 'posplayer' and click the link in his sig. If you work your way through the essential routine maintenance first, and check the charging system, you should end up with a good, reliable bike. Then you can think about upgrades like Jedz mentioned.

[Guest]

Progressive springs are a front suspension upgrade that will improve the handling.

Twin stoppers. Your bike has one disc on the front - it's not that difficult to install a second disc/caliper, leading to greatly improved braking.

530 chain conversion gives you lighter chain and sprockets. Not sure if you get a better choice of modern chains.

Pods replace the standard air filter on the bike.

Opened-up exhaust. You've already worked that one out.

R/R = combined regulator and rectifier. A weak spot on the electrical system of old Suzukis.

7/11 swap = replacing the 750 engine with one from an 1100 cc machine.

Probably the best place to start is Basscliff's site, along with checking the electrical system - find any post from 'posplayer' and click the link in his sig. If you work your way through the essential routine maintenance first, and check the charging system, you should end up with a good, reliable bike. Then you can think about upgrades like Jedz mentioned.

Actually Progressive springs are for the front and rear. A lot of us here at GSR use Sonic front fork springs, they are a straight rate spring where you can order a specific spring rate for your riding style. As for progressive spring stick with those in the rear shocks, as for using them in the front fork eh not gaining anything.

Your 81 GS750L already has twin disk brakes up front. You might need to over haul the calipers and install new SS coated brake lines. Same with the rear caliper.

Yes to the 530 chain conversion, well worth the investment.

Me, I would stay with the stock air filter set up, just install a K&N stock replacement air filter, and it is easier to tune with the pipe you have now. ( Didn't see the 4-1 first time around lol)

As for the RR the stock shunt setup is pretty much to be desired. Upgrading to a Series type RR (Polaris Sh-775 or a Compufire RR to name a couple Series type RRs) is the fix for this along with a good inspection, cleaning and replacing bad connections in your electrical system.

And when the time comes a 7/11 engine swap is one to drool over.

[Spyder]

No worries, We all started where you are... First, welcome to the site. Progressive springs are an after market brand of springs that eventually you will want to use to replace the wornout soft springs that are in your front forks. Twin stoppers, are what you already have on the front of your bike. Dual disk brakes, "stoppers".
530 chain conversion, the stock chain size on all of our bikes is 630, it's big, it's strong, and it's heavy. You can lighten thing up by a few pounds by changing your chain and sprockets to a 530 setup. Which is just as strong as the 30 year old 630 was. Not a nessesary expense, unless you need a new set anyway. Something to consider when that time comes. R&R, regulator rectifier. It is voltage regulator in your charging system that is a big weak spot on these bikes. Run through the "stator pages" on bassCliff's site. And finally the 7-11 swap. pulling the 750 engine out of your bike and installing an 1100 engine.

You already have a 4to1 exhaust on your bike. I wouldn't recomend pulling the baffle out of the exhaust, as that would require a rejet. It is however possible that you will need to do that anyway because of the setup you already have... Good luck, and don't be afraid to ask questions here!

[Spyder]

Sorry, this was answered twice now I see. I got half way through all that then got busy at work...

[Jedz123]

Argh its even the same color!! Jealous to the max...

I should have mentioned before you start to dive into upgrades to do the basic maintenance first. Valve adjustments are crazy easy to do on that bike due to the lock adjustment rocker arms.
Your lucky you got the dual brakes up front. Mine was just a single.., Back when they could get away with subpar braking on new bikes.

I'd stay away from the 7-11 swap for now. The bike change is drastic and can be overwhelming to an inexperienced rider.

Go through the basic stuff... If the carbs are sorted and the bike runs good make sure you check for fork seals, mine went through a couple sets. Also be sure your wheel bearings are in good shape. I had to replace those after 15k miles of me riding the old thing.

Also protect the carbs by running a stabilizer every tank! The only time I never did was when Id run a tank of ethanol free... Oh yeah that gas range on the L tanks sucked... I was looking for gas every 80-100miles.

[Crankthat]

On a tight budget the chain and sprocket conversion is a great call when you do need to replace.
Biggest advantage to that would be the prices are less on the parts. (As far as I am concerned)
Valve adjustment as mentioned above.
Clean your connectors (electrical) and get to know everything about the bike you can mechanical and electrical.
Chances are very high you will be working on it almost as much as riding it the first few years till you get it sorted.
Someone posted a link to base cliffs site?
Start reading there and copy the material you will need as your work progresses.
16 valve 750
Great resource for your projects.
Pay attention to the wood piece used in rebuilding the calipers.(brakes)
Will save you much hassle.
Valve adjustment is a must also.
Many original owners overlook this and damage results.
Have fun!

[Hoosier]

I see on the Sonic Springs website there are three options for GS750L:

GS750L 0.90kg/mm Sonic Springs
GS750L 1.00kg/mm Sonic Springs
GS750L 1.10kg/mm Sonic Springs

which size should I be using? Does it depend on my riding style or the conditions of the roads around here?

[Hoosier]

I've come to the conclusion that I need new front brake calipers for both sides, and suggestions for after-market replacements?

[Jedz123]

I'd recommend rebuilding with what you have. To measure is to know so if you rebuild you calipers with new pistons you'll know for sure the calipers will work perfect for you.


Link to an ebay Caliper rebuild kit(Just double check this one will work for your bike).

I would also replace all the rubber brake lines with stainless and put a newer style Nissin master cylinder on. This one came off a buel blast but common equipment on the Bandit 1200's, look for something like this:

Link to that too...

Brakes are critical, update them and you'll be glad you did when you need them for that quick stop...

I went this route on my GS750... It was night and day difference in stopping power and lever feel.