Recently Aquired an XJ900F

Hiya,

I have Recently Aquired an XJ900F

Do all the 900's have a vibration felt through the seat between 4 & 5 thousand RPM ? or is there something up with mine, she runs brilliantly, but im just curious to find out if this is normal

Cheers,

Rain Man

 

Hi,yes My XJ900 does this, it equates to about 60 mph in fifth gear,it disappears as you speed up or slow down.Balancing carbs might help alleviate it to less noticeable levels.Welcome to the wonderful world of XJ's, a much maligned and underrated Bike. :wink:

 

Ok, thank you & yes, from 60 mph through to 75 mph (4 - 5 thousand RPM on my bike) it vibrates, but above & below this, she is silky smooth, if im in this zone & decelerate or accelerate she still vibes until she is out of this zone.
Its gonna take some getting used to this lol
Other than the vibes, she is a Great bike, just gotta put some new Fork Springs in as the Originals have compressed over the years, so im bottoming out alot at the moment :/

Rain Man

 

As well as new progressive fork springs , one grade heavier fork oil makes a big difference, cheers , Murray

 

Cheers murray, i will bear that in mind when i change them

With Hagon progressive springs, do i need to make spacers for them or are they already the same length as the original springs would have been when new ?

Getting back to the vibes, will i hurt the engine if i ride in the vibe zone alot, cos, to be honest, i usually ride between 65 & 70 mph anyways, i just wanna be sure im not gonna hurt the engine ?

Cheers,

Rain Man

 

No need to worry about Engines their Bulletproof.Asl long as you change Oil and filters regularly youre good to go.If the Cam chain is in Adjustment all is good.The Primary chain can go thats an engine Tear down.If the Engine sounds like a Bag of Spanners when cold its a good indication of a Duff primary Chain.

 

Is it just like a slight buzz or like full on bar jiggle? Normally in that range our bikes tend to "hum" and that wont cause an issue. But i normally just ride faster.

 

Thanks SimonRef, my bike has only done 22464 miles since new, whats the average mileage when the Cam & Primary chains need replacing ?

My engine does sound a bit dodgy when starting up after its been left a week & the temp outside is below 8 degrees Celsius, but when warmed up, she sounds fine, i really don't wanna have to get it stripped down so soon

What tell tale signs should i look out for with the Cam & Primary chain wear ?

Yes, sometimes i can be quite paranoid, more so when i have not had the bike long :roll:

The buzz is only through the seat, my bars don't vibrate at all & yes when i take it past that rpm range, i find im at 90+ mph & i dont wanna lose my licence lol

Cheers,

Rain Man

 

At 22000 your Engines is hardly Run In .These engines are good for 150,000 miles if looked after.If you like giving it the Beans, change your oil more frequently maybe Twice a season.A loose Cam chain really shakes the Bike through.Transmission snatch is a good indicator of a primary chain on its way out,again on Tickover you can hear it thrashing away.Like I said at 22,000 miles youre in an Enviable position ,no need to worry just Enjoy your Bike.

 

I do have transmission snatch when riding, yet, when i put the bike on its center stand & try to feel it by moving the rear wheel forwards & backwards, i cant feel any snatch, i also dont hear any thrashing at tickover, even if i rev it a bit, man im really paranoid now :?

Cheers,

Rain Man

 

I really dont think you've got anything to worry about your Low mileage Engine indicates this.Vibration and transmission snatch could be indicators of carbs in need of balancing,if you are not happy with your engine try that you will get smooth pickup good tickover and hang on tight acceleration.

 

Cheers SimonRef, i have no idea if the carbs are balanced or not, the engine pulls like a train & feels very responsive, tho i have not tried a fast WOT, so i assume they must be balanced up quite well

Cheers,

Rain Man

 

Pics or it didn't happen :lol:

 

Here are 2 pics of my 1988 XJ900F on the day i rode her home





Cheers,

Rain Man

 

Nice tidy example! Check for rust at lowest point at rear of tank though....

 

I removed the tank & had a look at the rear bottom part of tank & there are no signs of rust that i can see, the paint finish is all smooth with no bubbling, so guess im ok

Cheers,

Rain Man

 

nice bike!

brakes ought to be looked over though, old lines, old pads, and check the date of the tires, anything over 5 yrs toss

Welcome RM!

 

Thank you, the brakes are fine, brake lines seem ok, no bulging, so i think im ok on that & i also put new tyres on her a few days ago, new brake pads will have to wait til the new year tho

Cheers,

Rain Man

 

Bulging doesn't tell the whole story...

http://www.xjbikes.com/Forums/viewtopic ... rakes.html

 

Point taken, thank you for pointing this out

Cheers,

Rain Man