Hi guys,

Just picked up my first real road bike last week, it's an 81' XJ650, and i'm loving it. Since the search function isn't working I need to ask the following questions:

Where is the idle screw(s) located? Bike won't idle without giving it a little bit of choke...

Where is the oil filter located? Is it external like on a car, i hav'nt spotted it yet. Also, which is the sump plug? Is it the one that is vertical towards the front of the motor. If so mine is vertually in-accessible due to the 4 into 1 system. Anyone have a similar problem?

My bike has adjustable Koni rear shocks. Currently they are on the lowest (stiffest) setting. I was thinking about raising the rear of the bike. Any tips on if this is a good idea? Also, how do you adjust them. Is it just a matter of un-bolting them and twisting them?

Any help greatly appreciated :)

It is supper time - will respond properly later.

The front thing in behind the 4-1 is the oil filter. This can be a pain in the ass - if you can loosen the bolt off you are fine... otherwise you know the hard way is the only way.

The sump bolt is hard to find - lie on your back - put you chin under the shift leaver and look up... yup - it's a pain in the ass too but completely doable.

Adjustable shocks - I've posted my understanding of this before but the long and the short of it is that you want to adjust to about 2.5 inches of sag for the conditions you will ride it - ie - just you adjust for that - add passanger and gear adjust for that.

Thanks woot, i look forward to your response about the idle. I will get under the bike tonight and sus out the sump plug and oil filter. I suspect they hav'nt been changed in a while because of there in-accesibility. I might have to take the aftermarket exhaust off.

I'll probably unblot one of the rear shocks to see how they work, from the early reveiws of the bike i understand that not all markets got the adjustable shocks...

Also, there is a loudish tick-ing noise that comes from the top of the motor, and increases in frequency with the revs. In one of the reveiws it says that the 'shims' need regular maintainence. Is this likely to be the problem? How critical is it that I attend to this?

Thanks in advance

I will volunteer a few answers. The rear shocks have stepped notches if they are adjustable. You do need a tool to move them, basically a semi-circle with a tooth on the end. You should be able to pick one up locally or at Dennis Kirk or the like. You don't need to remove them to adjust, it's done on the bike. Stiffer is fine, set it however you like the ride. Usually stiffer is better for more aggressive riding. If this is your first road bike, it may not matter too much. If I can make another suggestion, if you have limited street experience, go take a MSF rider course. It will be VERY worthwhile.

The ticking is very likely from one or more valves that need adjusting. They are shim and bucket style, and tricky to adjust if you have not done it before. Do it before riding it a lot, loose valves increase wear and sap power. #1 is to get a manual to explain things to you, with out it you will be lost and helpless. Once adjusted, the valves should be good for many thousands of miles.

With a 4 into 1 you may need to remove the exhaust to get at the oil filter. Sorry.

Idle adjustment is not so simple. You can turn the gross idle setting up and down with the adjuster wheel between the rear of the carb bowls. Fine adjustments involve the idle circuits and individual carb settings. You need to do the valves first, then synchronize the carbs. It will make a world of difference if it has not been done lately.

Does this group ever get together or organize any tech sessions? I am involved with other bike groups that do. If not, it might be a good idea. I would be happy to have one in my area if there are any owners in the Minneapolis/St. Paul zone that are interested. I have one torn down fairly far right now, doing carbs, forks, tires, valve adjust, etc. Most dealers will not work on something this old, and they tend to screw things up and screw you at the same time anyway. Far better to do it yourself.

THREAD JACK!
2Fast - I see you have an IBA # and a ninja 250 - you have to know some of the same crew I ride with - I'm Woot from the ninj250.com forumn and I have ridden with Duke, Leon and Andrew who are all ninja 250 owners who have competed on the 250 in the Iron butt rally. Infact I'm almost certain Andrew has a connie as well!

Last group ride I did was in NY with the Ninja 250 crew - great ride through the catskills, green and white mountains... the aderondacs SP??? Anyhow - if you haven't checked out ninja250.com ( or .org or .net) do so :)

Cheers,
woot.

ORIGINAL QUESTION
Setting suspension is generally harder is better - but there is a point where it gets too hard. When it is too hard some riders will say oh it feels faster but it isn't. The problem is you get chatter from the rear end - you loose traction because the tire is skipping bumps not absorbing them. If you adjust too soft then of course you get a mushy rear end and run into clearance and stability problems.

Do yourself a favour and adjust it properly. Here is how I do mine, but I'm sure there are other ways to do it. On those shocks you can adjust preload. The preload sets the shocks to sit at the rest height when the suspension is still. This doesn't mean crank it so that the shock is fully extended when you sit on it - this would mean they'd top out all the time!!!

So - stand over the bike and hold it upright. Measure the distance from the rear axel (or something solid on the swingarm near the axle/shock) to the frame of the bike.

Next sit on the bike. Have the helper measure the new distance. The difference is how much the shock has been compressed by your weight at neutral. This number is the sag. I set the sag at 2.5". That is what I was told to do. There must be a formula based on shock length and swingarm length... anyhow 2.5" is what I was told and it has put most of my bikes into the right ballpark for sag. Any less and I topped out, any more and I started to wallow. I found this number worked.

It is completely dependant on your weight too. If you add more weight then add more preload to keep the sag the same.

I've found I was able to adjust some of them by hand or with a screw driver - have a look... I don't think the right tool is too expensive.

Woot.

While where on the subject were is a good place to buy new valves.

Thanks heaps guys, I have printed this page so i can let it fully digest later on.

With regards to the shocks, it is currently on the stiffest setting and the bike handle great. But the bike from side on looks a bit odd, low in the bum, high in the front. Maybee that's just an XJ thing. Also the steering seems to be very light and moves around a bit whilst coasting, which I thought might be a result of this. Maybee to much front tyre pressure too, still experimenting.

2fast, no this is my second road bike, but my first bike greater than 250cc's. I did my learner licence on an RGV250 back in the days when there were no power to weight restrictions B) I will add my other bikes to my sig...

2fast, A XS1100E nice ride being the worlds fastest production bike a few years back.

I restore these bikes everyday. The Seca Turbo is my favorite but wouldn't sell the XS1100 for $10,000.

RE: the front end being funny.

Please post more on what it does - but I'll start with somethings to check.

It could be the head bearings are worn, or the head needs tightening.

Put it on the centerstand - put a friend on the pillion seat to get the front tire off the ground. Slowly move the front end side to side feeling for any notchiness. Pull it about and see if it has any free play. Free play can be fixed a bit by tightening the head to the proper torque (MANUAL - I don't know the value!) but notchiness means new bearings.

Next - look for fork oil seaping past the seals. This happens and it doesn't cost much in parts to fix. If the springs are worn out ( shop or someone else could tell you the value ) that would be a few more dollars. Anyhow - rebuild with fresh oil and perhaps spacers to add preload. Remember spacers reduce the travel the front end has - cutting the springs makes the springs harder too - I have heard of people cutting a coil or two off and then adding spacers. This maintains the travel distance but increases the stiffness of the front end.

I'd suspect the rear end is too stiff and causing more play in the front end ( stress goes through frame and effects the front end )

Also -- the maxim does sit back quite a bit - this is why the rear brake does more work than on a sportbike which sits quite forward.

After you check the forks/head then obviously check the front tire. If it is worn or worn strangely then replace it. If it is old replace it. Sometimes you can get a funny feeling from a strangely worn tire. I've found that the maxim will wear the edge of the tires funny, and as they get old you'll get a slight weave when leaned over.

For tire preasures I run 30 front 32 rear. Huge debate over this. One side says run high preasure to increase tire life, low preasure makes tires squish therefore heat more and therefore stick/wear more. The other side says low preasure increases contact patch size and wears more surface area - meaning the tire wears out no faster than a high preasure tire that wears out in one spot more quickly. Of course having a larger contact patch that may be warmer means it sticks to the road better. My personal beleif is that the later makes sense as I have seen examples of tires lasting really well with on-the-low-side preasures.

If your preasures are outside of 25-35 Front and 27-38 rear then you might want to adjust your preasure scheme - that's a very personal choice. One thing with the maxim's geometry, a low front tire makes the front tire very heavy to turn.

I'll stop there and get back to work... :) please add more info to the strange feeling from the front end ( like how you get it to feel weird )

cheers,
woot

Thanks again woot!

The steering problem is kinda hard to describe but i'll do my best. Basically, at medium speed whilst coasting (under power it is O.K) the bike requires almost constant correction to maintain a straight line, and if i take my hands off the bars it will drift to one side. It's not pulling to one side in particular either.

Anyway I will do as you suggest with regards to the testing the steering head bearings and adjust the tyre preasures and get back to you. Definatley no seeping oil which is good.

Here's a pic of my bike for reference...

OZXJ.

My bike has a 4 into 1 exhaust but I can get to the drain plug without too much trouble havn't been able to undo the bloody thing though. Tried the heat treatment no joy. I cant understand why there is a perfectly good sump drain with a Phillips screw through the middle of it, is yours the same?
I think getting the oil filter out may pose a problem when I manage to get that nut undone. I really don't fancy having to drop the exhaust given that every nut and bolt on the bike seems to be fixed solid.


Mick Fahey

Yeah Mick, alot of my nuts and bolts look like there fixed as well. I'm going to spray them with a penetrating oil and let them soak before I have a crack at getting them off. As for the sump nut, after having a closer look, your right, it is possible to get a socket on it. But as for getting the oil filter casing off, I will need to remove the extractors. No phillips head in the nut though Mick, don't know what you've got there...

Hey woot, I've got that floaty steering problem fixed, would you beleive the rear tyre was set at 40psi and the front at 45psi :o I'm luck they had'nt exploded on me! Now with 30/32 as you suggested, the bike rides great!

Mick: It sounds to me like you may have the same trouble as OZXJ. Sometime in the past someone has not been able to remove the drain plug. And they drilled a hole in the plug to drain the oil. Then simply put a screw into the drilled hole to act as a new drain plug within a plug. Just an idea, have you tried to remove this screw to see if the hole goes all the way through?

EXCELLENT OzXJ!

Sounds like you were riding a pogo stick! :) What you were probably feeling was ultra light handling! Ever ridden a sport bike? The first time you ride one you'll get that feeling... after awhile anything but that feels like a snow plow.

Sorted!

You could well be right Woot about the reason for the screw but it is shown on one of the websites, possibly oldbike barn.com. Anyway a three day soak with wd40, some really foul language and the threat that I would send the wife to deal with them brought them round.

The filter almost fell out, no trouble at all getting it out and replacing it. The oil was black and filthy I doubt if it had been changed for years.

I think a new rear tyre and silencer and I'll be ready to try getting her registered over here. l A long drawn out and costly business I'm told.

Mick Fahey.