Normal Speed?

[Anonymous]

My 1978 GS550E is topping out at around 50mph. I have a timing issue that I need to check and possibly a carb issue I assume. What is the normal top speed for these bikes?

[gspaul]

About 110mph,so yea check ignition and valve gap,carby's last.

[Griffin]

If it's in a good state of tune, it should be able to hit 100 mph, perhaps a bit more. You should be able to zoom it right up to 90+ mph no problem.

[Anonymous]

Thanks for the info, guys! I have never been under the covers (so to speak)...how difficult is a valve adjustment? Conversely, how expensive would it be to have a shop do it?

[gspaul]

Shop work is not cheap,buy yourself a manual(ebay?),and any other detail's you need we can help you with .
They are not hi tech bike's,I am sure you can do it.

[SqDancerLynn1]

The GS bikes are terific & can give you hours of fun BUT you need to get a manual & learn to do your own work. Most dealers won't work on our bikes so that leaves the independent shops. Personally I would not stand
having the bike in the shop I hear stories of 3-4 weeks??? to get work done. To do the valve adjustment you need cam cover gasket, 1/2 moon end plugs $35 Tappet tool $35, elect dial calapers (Not mandatory-local auto parts $20).. You should be able to get all for less than $100
+ $10-20 for shims if any are needed. Usually only one or two will need replacement

[Anonymous]

Again thanks! I really think I will buy the Suzuki manual, I'm sure that is the best. Are the shims sold at the dealer?

[gspaul]

Yes they are,but when you check the gap's you can often swap them around to get the right clearence, so you may only need a couple.

[Anonymous]

Depending on the personality of your local Suzuki dealer, you may be able to rent the lifter depressor tool plus an assortment of shims. As long as he gets the same amount of shims back, you may only have to cover the rental. Worked for me at Modern Suzuki in Vancouver, BC,(plug for Murray here!). You definitely need the FSM and a valve cover gasket, though, although you may get away with re-using the half-moon end plugs.
Tip: Spray or wipe the new gasket with WD-40 or equiv., that makes it re-useable for a time or two. \/

[bwringer]

YMMV, of course, but NONE of the Suzuki dealers in and around Indiana stock the shims. I've called them all. Be aware that Suzuki dealers are usually a dead end.

I believe the shims are still used in the GS500, which is still in production, but the dealers are too busy selling GSXRs to the baggy pants crowd to actually stock parts for smaller/older bikes. Most will flat refuse to look at or work on older bikes.

I buy shims from Cycle Recycle II, which is only about 20 minutes from my office. You can also get them from the CRC2 web site here for only $5 each:

http://www.crc2onlinecatalog.com/

You may also be able to find shims at your friendly local independent motorcycle shoppe.

[Nerobro]

110mph is normal.... Do you still have the airbox on the bike? Do you have the stock exhaust?

[Anonymous]

The bike is totally stock mechanically. The only things that are not stock are the mirrors and the front turn signals and some fork gaiters. Interesting thing happened today while I was out for a spin. The bike was doing the usual no power and backfiring thing while I was climbing a hill. I turned the throttle up out of desperation and the bike suddenly sprang to life and took off like a bat out of hell! It has been running fine ever since. My latest theory is that there may be some rust flakes or some other sediment in the tank that clogged one or more of the carbs. Whatever it was worked its way though and now the bike is fine. I am thinking an inline fuel filter should be next on my shopping list. Thoughts?

[gspaul]

As the fuel is gravity fed, inline filter's are not the go.
Clean out the tank,petcock,and the filter in your tank.

[Anonymous]

I thought the petcock was vacuum operated. What is the proper way to clean the filter in the tank? Are new ones available from the dealer?

[gspaul]

The petcock is vacumn , but you should still clean it out.
Remove your tank,drain the fuel.
When you turn the tank upside down you will see two bolt's holding it on.
When you pull it out you will see the filter it's a part of the petcock,you will only need a new one if it's damaged,otherwise just clean everything up.