High speed wobble

My friend wants to go 100MPH. He says at that speed his Harley has a wobble. We are mulling it over. I've sugested swing arm bearings, shocks, forks and steering bearings. He has thought of tire ballance and alignment. The short answer to what causes high speed wobble is: yes all of the above. He tells me that his wide glide is notorious for it. He has a narrow 21" front tire from a different Harley. That lets in wheel spacers. He has recently gone back to the mild cam. His cam bearing failed and chattered the screaming eagle cam journal (not the lobes). Harley wasn't interested that their $4.95 bearing ruined an expensive cam.

Is this bike a twin cam? If so, American Iron mag did a series of articles a short time back about these very issues. It seems the twin cams have some teething probs. And the motor company doesn't really want to own up preferring to let warranties deal with them as they arise.

Is this the article, Dgrason?
http://www.aimag.com/downloads/TwinCamUpgrade.pdf

I did a search on screaming eagle cam and found:

http://www.cyclespot.com/harley_parts/prods/HTDFLSCR.html

I guess it has to be a twin cam cause the pushrods don't go to the same place. When he takes it up to 100MPH, I'll just go as fast as I want maybe as much as 85 or speed limit + 10%.

We are going to Mt. Rushmore. Just throw in a sleeping bag, tent, three changes of clothes and go. It is funny that that plastic company (Visa?) had a security breach. I hope it doesn't screw anyones vacation.

The bike is a evolution motor, single cam. The wide glide front end is not a complete change-over, it is still using the 39mm tubes that were stock equipment. The only way to go any faster is to power through the wobble , which can be very scary at that speed. It seems to go away at about 115 mph, but at times it seems to have to go even faster than that to clear up the wobble. The balance on the bike is excellent and it handles like a dream, so I have ruled out alignment problems. Any information is appreciated.

Is this the article, Dgrason?
http://www.aimag.com/downloads/TwinCamUpgrade.pdf

No this isn't the article i was thinking of. But it is close. I'll see if I can dig it up.

Hi,
Check the fall-away on your front end,but grease the steering head bearings first,it should be 1 to 2 inches max.Check your manual for the procedure!!!!Good Luck........."AL"

Hi,
Check the fall-away on your front end,but grease the steering head bearings first,it should be 1 to 2 inches max.Check your manual for the procedure!!!!Good Luck........."AL"

Welcome to the forum.

Thanks

Hi,
Check the fall-away on your front end, it should be 1 to 2 inches max. Check your manual for the procedure!!!!Good Luck........."AL"

Fall-away on the front end of a Harley Davidson? I don't want the front wheel to fall-away! I wonder it the guy doing the trick riding on the bike with no forks or front wheel is the same one that got caught selling stolen parts? Daniel Duest http://us.rd.yahoo.com/dailynews/rss/search/motorcycle+parts/SIG=129i5qu51/*http%3A//www.milforddailynews.com/localRegional/view.bg?articleid=94159

Here is a good article on fall-away:
http://www.hdforums.com/m_90127/tm.htm

Warning:"Properly adjust fork stem bearings. Improper adjustments affect stability and handling, which could result in death or serious injury".

here is another article having more closely to do with fall-away method of pre-load:

http://www.v-rodforums.com/forums/showthread.php?p=327922

Some of it will apply to BMW and the BMW "wedding band".

Yeah! Fall away is when you check the pre-load on the steering head bearings.Here's the procedure...jack the bike up to make sure it is level,remove the clutch cable,and lever from the handle bars.Place a piece of tape on the front tire.Grease the steering head bearings,providing you have a grease fitting in the steering head frame,which you should have,after greasing the bearings,move the front end right to left several times making sure the grease is dispersed into the bearings.Place the front wheel at the center where it feels neutral,using a pointer line it up with the tape,tap on the side of the tire to the right,when it starts to fall away mark that spot on the tape,once again bring it back to center where you find the neutral spot,tap on the side of the tire towards the left,when the wheel starts to fall away place a mark on the tape.Now measure between the two marks,and it should be 1 to 2 inches to be in specification. Does that clear everything up:moped:

Just wondering if it could be engine or drive line harmonics. I know that I have had several different bikes that had a "critical speed" where it would vibrate.
Ride Safe,
Tugs

:signgood: Yes!, Thank You!, I had not thought of that. And Thank you all!