Rossboyd asked about front end wobble, trying to help out a newcomer...

[cowpuc]

First off, let me say to VR @Rossboyd.. Now onto the question you asked in the shout box.

 

Couple questions about your question just for clarification.. By "low speed" are you talking about the infamous 25 to 40 mph wobble? I am assuming that is what you are asking about - THAT has been a common problem for many of us 1st Genners. Personally, I have had 5 of the early models and have dealt with it on a number of them. IMHO, that nasty wobble that keeps us from being able to stand up and go no handed at slow speeds is a pain in the neck and one of the downfalls of the 1st Gens.

If I were going to attack solving the problem on your scoot I think the first thing I would do is smack the brake calipers with a rubber mallet - couple wacks each on the exterior to make sure they are loose/not dragging and then see if the wobble goes away by riding it before you hit the brakes and reset the calipers, might sound crazy but I have found that brake drag can cause that wobble.

I would also check is the front tire - center stand it - spin it and see if you can feel or see wear. Look for cupping and distortions or anything that does not appear correct. Nock the calipers loose again and check wheel bearings for movement. Also check air pressures in both tires. Also, it is possible that a front tire/wheel balance may help BUT (and this is just my opinion) most unbalances from a tire seem to become more noticeable at high speeds = low speeds like we are talking usually mean something else is wrong.

Next would be neck bearing torque, that setting acts a lot like a steering dampner in many respects. Because of the weight on that bearing it is VERY common for it to be out of spec on one of these beasts.

Also, how are your fork springs? Sacked out springs (this is VERY common) can also cause it - Progressive Springs and a fork oil change can also help a lot. Also,, the bushings in the fork legs that guide the upper tubes thru there movement can become worn to the point that they allow fork movement which can cause issues like we are talking too.

If you look between the fork legs above the front fender you will see a chunk of aluminum that binds the forks together. This serves as a fork brace to stabilize the front end. Maybe double check the bolts holding it in place (never found a loose one but it could happen). Many of us have gone to a heavier brace, I think we even had a member or two here who actually made these - @Carbon_One (REALLY GREAT GUY!!) comes to mind - may be wrong but even if I am he is still a great guy and a good friend. In the end, and if you can find one, you may find one of these to be of assistance..

Good luck on your endeavor to be rid of the wobble! Post up here to let us know that you got this! There are MANY folks on here with lots more experience in solving the problem you have touched on - we can get some of them to chime in!!

All the best!

Puc

[Carbon_One]

Rossboyd, Puc is right about looking thru all the clues for finding the cause of a wobble. However he is wrong on the one count of it being me making fork braces. I'm not sure just who does but someone will come along soon letting you know.

Sure hope you do find out what's going on as it can be frustrating chasing down problems like this at times. Good luck, Larry

[Goose68]

Condor makes the brace

[camos]

Condor makes the brace

Condor USED to make the brace but, no longer. There were some 1" thick braces available on eBay perhaps 6 months ago. I have one and it works very well. The Super Brace will likely still be available on eBay, it is 2" thick and costs twice as much as the one I bought. A thicker brace is a good thing but probably not the first solution to try.

 

I didn't see the original question so here are some things to look at:

My 90 VR had a loose head bearing when I got it, that only showed itself when crossing from the road to my driveway at an angle and when travelling in a curve at over 65 MPH, but not in the parking lot or other slow speed maneuvers. The head bearing should definitely be set, takes a bit of time but it's free.

 

As Puc said, a dragging front brake could cause a bit of wobble. My suggestion is to lift the front end and spin the wheel. It should spin freely and come to a stop smoothly. If the brakes drag the spin will either not happen or will end abruptly.

 

The forks may be out of whack, uneven oil level or plugged valves. Older bikes with no service record should have all fluids changed which includes the fork oil. (every two years?) If the wheel and axle are removed the forks can be extended and depressed individually which might indicate a significant difference in their action while a subtle difference probably would be difficult to notice. A subtle difference is not likely very critical at slow speeds but might be more so on bumps at speed.

 

The rear swing arm and linkage bearings/bushings are often neglected and can become excessively work from lack of grease. I think this would likely be most noticeable in a hard turn at speed.

 

Cupped tires can act in a manner similar to uneven road surfaces and cause slow speed steering deflections which might be described as a wobble.

 

Can't think of anything else to add to what's been said before.