Dif between my 78 and 79

[tri650]

I have a 78 xs that absolutley rocks. Fast and incredibly smooth. In fact, one of the smoothest bikes I have ever owned - you basically feel very little vibration as you move up to 70-80 mph.

Now, I just picked up a 79 for an incredible price and what a difference. I could really feel the vibes through the seat and handlebars. Not as fast and definately not as smooth. The seat vibes basically put my rear to sleep in about 30 minutes.

I know that balancing the carbs does a lot to control the vibes - learned this from my 95 concours. Also the 78 has new tires - the 79 tires are not good.

Anyway, I guess I have experienced what a difference a well tuned xs11 can feel like. I could not wait to get off of the 79 and back on my 78. Wondering if there are any other tricks I missed that make the 78 so much smoother than the 79 - other than carbs and tires. Anyone?

[trbig]

Did you check for loose/worn motor mounts? Also.. I'd check the U-joint. It's probably original and never had a squirt of grease on it. When mine started going bad, the bike got a weird buzz/vibration to it for quite a while. I was afraid the crank had wallowed out the bearings again.


Tod

[CatatonicBug]

Might also try a fork oil flush. Take them apart and wipe the insides down, and give them a fresh fill of oil.

The tires will definitely make a difference though.

[dbeardslee]

I've got a 79F that's smooth as glass. The thing that probably paid the biggest dividends in terms of 'smooth' was reworking the head - valves cleaned and lapped, ports cleaned, new stem seals, and valve clearances set. You might do a compression check to see if your motor would benefit from a head job. Of course that assumes that your carbs are dialed in and properly synced. The other thing that's almost always an issue with a new old machine is the electrical connectors and the good old pickup coil wire fix. Cleaning connectors is a good start, but for a really first class job you might consider cutting a little off the end of each wire and crimping new connectors on. I did it on mine, and recovered a full volt at the TCI - and that was after they had all been cleaned. A digital multimeter comes in real handy for checking the condition of your electrical system. Just some more stuff to think about when you're done with u-joints and tires .

[skids]

The vibration can come from metal-to-metal contact between the frame and the pipes.

[Rickrod3]

My 79 is smooth

Hey:

I also have a 79F.
I find it to be remarkably smooth especially @ 70, 80 MPH.
I do get a little vibration @ 35mph from the front end that I feel through the handle bars.
Just got it running a few weeks ago still a work in progress.

Rick

[yamahansolo]

my 79 screams and it's smooth

[b.walker5]

Who has the comment in their signature about these being a growling badger. Best description I've ever heard, and certainly fits mine. Has a vibration around 110 to 120 km/h (55 to 65mph) and is a little rough around the edges when compared to a new bike, but if I wanted the feel of a smooth new bike I'd buy a smooth new bike.

[jmnjrpa]

That

Quote was from Trainzz, may he rest in peace. Others have picked it up as it is a good one.

[dbeardslee]

growling badger. Best description I've ever heard

Down there in New Zealand I would have expected "angry apteryx" to be the description of choice .

[b.walker5]

LOL, you've obviously never seen one of those things angry. Theyre card carrying pacifists, that why they're almost extinct. "Sure Mr Rat, you can come in and eat all my eggs, I'll just sit over here in the corner with my eyes closed so I don't know its happening" Theyre as dumb as a friggin door knob. God knows why they were chosen as the national symbol, 'cause they truly dont reflect the nature of the human 'Kiwi'. The Tuatara or the Kea would have been a better symbols, at least theyve got some fight in them.

[psycoreefer]

That is one mean looking bird. Hard to tell in a picture, how big are they?

[foreda]

79 F Vibration

Do you have the original exhaust on the "F". My 79 F Standard has the original system on it and there is some noticeable difference between it and my 78 E. The 79 has more of a rumble with the stock exhaust that causes a little vibration in the pegs but that's about it.

[b.walker5]

That is one mean looking bird. Hard to tell in a picture, how big are they?

About 18 to 20" tall and weigh up to about 2 1/2 lb. Neat critters to watch and be around but they're diabolically destructive. Heres one doing what they do best.



They're very nosey and extremely intellegent. When I was a kid I used to go on a lot of Scout camps in the mountains around where I lived. A favourite trick was to get a small jar with a screw lid and fill it with bits of apple or other fruit, and then throw it to the ever present Kea and time how long it took them to figure out how to unscrew the lid. Usually they had it within 10 or 12 minutes, but ocassionaly you'd find an impatient one who'd pick it up, fly up a few feet and simply drop it on a rock. Plastic Jars used to piss them off. If you didnt like someone on the camp, or they were new to the outdoors, you'd make sure one of their boots was left out overnight. 9 times out of 10 the boot would be gone in the morning, but if it wasnt the laces surely would be. They'ed never be hard to find though, albiet with a few holes, once a Kea figures out he cant eat something he loses interest fairly quickly.

Sorry, shouldnt be hijacking the thread with this stuff, so heres a wiki link with some pretty good info for those interested in more

http://en.wikipedia.org/wiki/Kea