Opinion on understeer

[jknappsax]

I have been getting my "new" 1979 GS1000 back in shape, and took it out for a ride the other day. Now, the carbs aren't right yet, but they're getting close. My question for you out there has to do with understeer compared with my 1978 GS750, which was set up with Progressive fork springs, E style mags front and rear, and Conti RB2/K112 tires. The 750 handled excellently considering it is 30-year-old technology. The 1000 has Ikon rear shocks, spoked wheels, and Kenda tires. The wheel bearings, steering head bearings, swingarm bearings, and tire inflation and balance all seem good. Any opinions on what I might be running into here?

[simon kuether]

Have you checked that your wheels are aligned properly?If your back wheel isn't true to your front,wierdness will happen.Cheers,Simon.

[1980GS1000E]

Understeer is not really possible on a motorcycle ridden on the street by an average rider. If the front tire is slipping, get a new tire. There is usually a vague feeling on these bikes when compared to a modern sportbike.

[tone]

I experianced mild understeer which turned to major oversteer on my old 1000s if it was pushed hard (Eg most of the time )

my solution after a months of messing with oil levels & weights etc was to drop the forks through the yokes by 10mm this alone made the front end much more secure & planted on the road under any conditions

i wont go into the exact fork oil & air pressure setup that suted me as every rider & riding style is different but will say i used the correct oil but messed with the level to suit myself

another thing ive found the gs to be sensitive to is front tyre condition & pressure so thats well worth checking too

hope it helps :-)

[Zook]

Smaller tire diameter will quicken the steering also.

As said earlier different tires and compounds will affect handling greatly.
If you want a great handling bike don't cheap out on tires. You will get what you paid for.

[JayH]

What front tire is on your 1000? Could be that the tire you have on it is more of a "triangular" type of profile and it turns in much easier compared to a "rounded" profile tire.

If your tires have cracks, uneven wear, etc. get some new ones.

[jknappsax]

The front tire is a Kenda, and by understeer, I mean that it swings wide when you turn into a curve, not turns in easier. The tires are in good shape, a round profile, proper inflation. The Kendas came with the bike; I wouldn't have put cheap tires like these on any bike. The bike currently has a 4-1 header that has hit before (dents in pipes 2 and 3), so I don't want to try to slip the tubes up in the triple-trees due to less-than-adequate ground clearance. The tire isn't slipping, it feels more like fork flex, but checking that the front and rear are lined up properly is a great suggestion. Do you think the spokes vs. the mags I had on my 750 might be causing the vagueness I'm feeling? I know a lot of riders with GS1000s, and they seem to handle fine. I've been riding my 750 with GS1000s since they first came out, and never heard any of my friends with this complaint in the past 30 years. The GS750 and the GS1000 of the eight-valve variety are almost identical in terms of weight, wheelbase, frame construction, and almost every other respect. I went over to the GS 1000 because it seemed that an extra 250cc with no weight penalty was a no-brainer. All the GS 1000s I've ridden with did not seem to have this issue; at least no-one ever mentioned it, and it didn't seem like it from how they could ride them in the twisties. I'm putting a GSXR1100 front end and wheels on it next winter, but I'd like to get to the bottom of this issue before I make any more changes.

[JayH]

Maybe the spoked wheels on the bike aren't running completely true?

The spoked wheels need maintainence compared to mag wheels. Your spoked wheel isn't subject to as much maintainence as one a bicycle but spokes can loosen and cause the rim to not run true. If you hit a pothole at speed it is possible to put a ding in the rim which would also cause the rim to not run true.

[76FJ55]

I noticed you mentioned the rear shocks have been replaced on the 1000S. If they are any shorted than the OEM shocks it could cause both the low ride height (dented pipes) and increased steering effort (increased trail); just a thought. If you have a lot of sag in the rear you will get the same as short shocks. itf you have adjustment left try increasing the rear spring preload, and see if that changes anything.

[jknappsax]

I replaced the OEMs with the IKONS, and they looked to be exactly the same length as the OEMs, but I'll go back and measure to make sure. Thanks.

[GSBuilder]

I experianced mild understeer which turned to major oversteer on my old 1000s if it was pushed hard (Eg most of the time )

I think this would cause an overload in the pants department (read: I think I'd poop myself)

Although, I've experienced similar pushing too hard with my modified suspension... it wasn't major oversteer, just sphincter tightening.