Back on the road! But with issues, and questions...

[SpannerMonkey]

It's about time I got back on 2 wheels, been off the road a few years and finally got my first 'Big' bike, a Yamaha XJ900

Gorgeous bike, had a lot of work done to it recently by prev. owner but there's still bits to do to keep her going.

1. The clutch is slipping under high power. For example, in 3rd gear, if I wind the throttle open fully, she'll climb the revs as normal but around 6,500rpm ish, the clutch lets go until I use less throttle or change up.

In all fairness, I'd rather a Garage do this work but buying the bike itself has drained what little finances I had. I've watched a few videos on how to change the clutch plates and suchand I'm tempted to give it a bash, order some friction plates and new springs. Question is, how easy is this job to fuck up? I'm no moron, but I'm no professional either. any do's or dont's here from the pro's here at BCF?
(Out of curiosity, roughly how much would a clutch-refresh cost at a garage as a guess?)

2. Battery keeps dying after a night time ride.
If I ride her during the daytime with no lights, she starts up first time every time and holds a passable amount of charge. If I got for a night time ride with lights on (including spotlights the prev owner fitted) she'll be fine all night, until I try and start her the next morning and she's dead.

The two things I'm suspecting here are the battery, and the spotlights.
The battery seems strange as it looks immaculate. no age related marks, residue or staining.
The spotlights seems to be my gut instinct and I'm wondering if they're drawing more power than the bike can technically charge.
What do you reckon to this one guys?

3. Sticky throttle.
Admittedly, this was one I didnt care about as its actually been saving my wrist a bit... until I realised the MOT is due in 2 DAYS!
I havent really taken a look at the throttle assembly, but the cables look fairly new and I'm making the assumption it's more likely to be the throttle assembly?
I did notice there seems to be some black tape underneath the throttle which may be interfering?
Any suggestions of various checks to accurately diagnose this one??

To those that answer, thanks for your time and patience, very much appreciated
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My bike? A YX140 powered one-off Monkey Bike, something a little different!

[Robby]

Easy enough things.

1. Clutch. It's fairly simple to change a set of clutch plates, the haynes manual has a step by step process. It does take a little while, I would expect a garage to charge 2-3 hours labour.

2. Electrics. If the battery is new and it's flat in the morning, then it looks like the bike isn't charging it. Usual reason is a blown regulator/rectifier. They die sometimes.
To check if it is charging, put a multimeter across the battery terminals with the engine running, multimeter set to volts. You should be looking for about 13-13.5V on tickover, rising to around 14.5V at 4000 rpm. If the voltage goes down as the revs rise, it is likely that your reg/rec is dead/dying.

3. Sticky throttle. Usually down to a bar-end being snugged up too tight against the throttle grip, causing it to drag. Could also be crap underneath the throttle tube, particularly if someone has sprayed some WD40 in there to ease it off.
Under the throttle tube it should be clean and dry. WD40 and similar turns sticky and attracts dirt, making for a nice sticky sludge. Look at the throttle tube for anything catching before you start looking deeper.

[MCN]

Hi and welcome back to biking.

Clutch may be something simple like adjustment of the cable.
I would expect a clutch slip in lower gears where there would be more load pulling away etc.

The electrical issue could be anything.
You need to find out how much load the lamps are drawing.
If there is no simple access to see the numbers on the lamps you can measure the current using a meter.
Easy-way (with more posher tools). You can use a clamp-on ammeter around the main battery cable and switch the lights on.
More involved-way. Connect an ammeter (one with sufficient capacity for the expected current) in series between the battery positive and the battery positive cable (red one). Switch on the lamp/s and see what the draw is.
If you find the specs. for the bike it will tell you how much electrical load the alternator can drive. As you possibly know, bikes are piss poor at driving much more than the OEM lights and ignition systems.

The tape on the throttle is sure to be the issue.
Probably a big diameter throttle has been bodged to fit a small diameter bar.
Make sure the parts are OEM for the bike and for it's Serial No.

I had a problem on a BMW R1200GS where the throttle stuck open when the heated grip was on setting II. The heat caused expansion of the grip which then squeezed on the inner sleeve. Just shitty parts.
Manufacturers use a term 'Stack up of Tolerances'.
Parts are made to a size plus or minus a bit.
It makes parts cheaper to make.
Sometimes a part with a + tolerance is fitted inside a part with a - tolerance and you have a problem.
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

[chris-red]

1. Easy to do, if you do it, while the bike is on the sidestand you can usually get away without changing the oil too. Only tricky part can be making sure the mechanism that operates the clutch is installed correctly. Check it works before bolting the casing up fully, remember you will need to adjust the cable with new plates.

2. Put a multimeter on the battery and let us know the voltages with the bike off and the bike running.

3. Easy to do, can be as simple as a bar end interfering with a grip, just be methodical start by looking at the grip end if you can't see anything obviously disassemble it and grease/oil everything and put come oil down the cable. If that still doesn't help you'll have to get the tank off and it could get more complicated.
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Well, you know what they say. If you want to save the world, you have to push a few old ladies down the stairs.
Skudd:- Perhaps she just thinks you are a window licker and is being nice just in case she becomes another Jill Dando.
WANTED:- Fujinon (Fuji) M42 (Screw on) lenses, let me know if you have anything.

[Vincent]

If you can get the bike to B75, I can help you with the Clutch and throttle and stuff. I'm only here one week out of two though.
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Space Is Deep

[SpannerMonkey]

Thanks for the tips there guys, Refitted a charged battery today, Multimeter during running was showing around 14.4v, and when I switched lights on, shot up to about 15.6v and the engine noticably dropped in revs, I have since removed the bulbs in the spotlights and she's running much better with the lights on now.

Also turns out the sticking throttle is due to a cable that seems tight only when steering is on full lock. Doesnt stick during normal turning positions or straight on.
Revs dont rise when I turn the steering, it just makes the throttle a bit stickier so a possible reroute is in order.
One thing I've noticed since I've removed the spotlight bulbs, is my sidelight no-longer works. The case may be that it wasnt working in the first place and I didnt notice but now I'm worried I've disrupted the slidelight electrics by removing the bulb.
I'll replace the sidelight bulb and see what happens as MOT is on monday :S
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My bike? A YX140 powered one-off Monkey Bike, something a little different!