maintenance q's

[erik]

I'm planning on doing some maintenance on my bike this weekend. Oil/filter change, change the coolant, change the brake fluid, possibly a new chain, check the valve clearances, have a look at the clutch (it kinda rattles a bit when the clutch is engaged and it's in neutral, but I guess that might be the gearbox. It's not loud though, so hopefully nothing is wrong. I'll probably just pull the side cover off the clutch to see what it looks like for fun ). I've just got some really basic questions:

Do I have to use distilled water in the cooling system, or is filtered tap water ok? If I should use distilled water, where can I get it?

Can I just get the brake fluid and antifreeze/rust-inhibitor from a car parts store (where I'm hoping it'll be cheaper), or is bike antifreeze and brakefluid different to that used in cars? (I know I'm supposed to use DOT 4 brakefluid in my bike, it says so on the reservoir cover, and that's what a general bike manual recommended).

And a not-so-basic question: My bike seems to run kinda rough/gutless at a medium throttle setting. I'm not sure if it's at a specific throttle opening, or at a particular engine rpm, or maybe a combination. But it sounds funny. I'm wondering if it might be a bit rich in the mid-range, and if lowering the needles in the CV carbs might lean it out a wee bit and help? The needles are held in with a plastic washer and a circlip (snap-ring) and iirc they seem to have additional grooves in the needles so that the circlip could be repositioned and the needle lowered. Has anyone tried doing this? I'm guessing if I'm careful it can't hurt, right?

TIA

[White trash]

Coolant and brake fluid are no worries, just use what you get. I've never used distilled water but then maybe I should. I've only ever used that in battries.

As to your running problem, I have no clue. Jap import 250s are notoriously difficult to set up and tune and 9/10 times is made worse by playing with them.

Good skills for wanting to undertake the work yourself though.

[RiderInBlack]

Do I have to use distilled water in the cooling system, or is filtered tap water ok? If I should use distilled water, where can I get it?

Can I just get the brake fluid and antifreeze/rust-inhibitor from a car parts store (where I'm hoping it'll be cheaper), or is bike antifreeze and brakefluid different to that used in cars? (I know I'm supposed to use DOT 4 brakefluid in my bike, it says so on the reservoir cover, and that's what a general bike manual recommended).

I as near 100% anti-freeze in my bike. Have rain water I can use if it's a bit low.

DOT 4 is the same for cars (you can even use DOT 5, but you don't need to). The important thing to remeber with Brake fliud is the it absorbs moisture so it goes off once it is opened. It is not a good idea to use any that has been opened and lying around for a few years.
Anti-freeze/rust-inhibitor is also the same as cars (I had a coolant leak in the VFR and just picked up the Anti-freeze from the service stations as I needed it).

[merv]

Agree with WT I just buy all my fluids from Repco because they are handy to where I live and I don't think I've seen a bike manual yet that recommends distilled water for the radiator. Just one pointer I've found with watercooled bikes it seems no matter how well you drain them through the normal drain outlets they must still retain a fair bit of coolant in the engine as they never seem to take the specified quantity to fill up. So what I do is mix the coolant with water 50/50 (or whatever brew is recommended for your bike) in a bottle and then tip it into the radiator so you get the right ratio. With cars I just used to pour the glycol antifreeze in and then top them up with water and the volumes were OK. Do that with the bike and you may have too much glycol and not enough water.

Changing brake fluid take real care bleeding the brakes properly so you don't get any air in the system - handy to have someone helping pulling on the lever while you are undoing and doing up the bleed screw - and you know don't let the stuff get on your paintwork eh!! Make sure you cover the tank with something or take it off when doing the brakes.

[White trash]

I as near 100% anti-freeze in my bike. Have rain water I can use if it's a bit low.

RinB, I don't think you're supposed to use antifreeze only in cooling systems. I can't remember why but I think it may have something to do with not absorbing heat as well as water. Hence the reason you use a mix of both.

[merv]

RinB, I don't think you're supposed to use antifreeze only in cooling systems. I can't remember why but I think it may have something to do with not absorbing heat as well as water. Hence the reason you use a mix of both.

Agree, I've never seen a manufacturer recommend a stronger brew than 50/50 with water.

[erik]

Thanks you guys for your advice .

I spent pretty much the whole weekend working on the bike, most of saturday cleaning it and pulling it apart a bit, and then half of sunday changing the oil and coolant, and changed the brake fluid on monday evening.

I didn't end up checking the valve clearances because the cover had one of those rtv silicone gaskets and it wasn't going to come off without damaging the gasket, and since I don't really know what the clearances are supposed to be, or how to adjust them (from what I've read, I'm guessing it's going to need shims to adjust them), I thought I'd better restrain my curiosity and leave it alone...

Changing the brake fluid, I was surprised how many bubbles came out of the front brake system. Does anyone know how they could've got in there? I haven't had the brakes apart or messed with them at all until now. I do remember thinking the front brake started to feel a bit funny half way through a trip from Auckland to Leigh and back, but I'm not sure if I was imagining things, or if that's when the problem started.
Anyway, with the new brake fluid, it's slightly better. It still feels like the brake lever comes in a fair way, but the brake does feel more solid.
I bled the brakes, like it suggested in a bike maintenance book, by pumping the lever and holding it, then releasing the bleed nipple/valve thing and watching for bubbles in the tube, and then repeating, all while making sure the reservoir is topped up. But the only bubbles I noticed came out when I was first changing the brake fluid. Anyway, I guess it's ok.

I had another look at the plugs, and as usual, they were all carboned up (well, there wasn't much carbon on the ceramic insulator, but there was on the metal bits around it). Anyway, I tried lowering the needles in the carbs, they've got 5 notches in them and have a plastic washer with a circlip above it that goes in one of the notches, and then it just slides through a hole in the throttle slide and a spring simultaneously holds the needle in place and pushes the slide closed. So I moved the circlip up one notch so the needles were a bit lower. Riding it I've noticed a definate difference; it no longer makes the "blaarrrgghh" sound at mid throttle/revs. I'll check the plugs again soon to see if they're staying cleaner. It's not all good though, as it seems to need more choke to start now, and (this might just be my imagination) it might not be quite as powerful at full throttle, but I'm not sure about that. I'm also going to see if I get better milage with the needles like this .

Anyway, I'm happy with how everythings gone .

P.S.
Does anyone know what the thing in the photo is? I unplugged it and forgot to plug it back in when I fired the bike up for a test run, the bike seemed to go ok, I only noticed it was unplugged later. I was a bit worried I might have damaged something by leaving it unplugged, but it's going ok now, so I guess it's alright. Still I'm curious...

[wkid_one]

(you can even use DOT 5, but you don't need to).

I wouldn't use Dot 5 - it is more hydroscopic and needs to be changed more often apparently. I don't think ANY manufacturer recommends DOT 5

Changing brake fluid is a good time to put braided lines on also.

Get a large syringe from a doctor to remove as much of the fluid from the Master R as possible - this will make bleeding properly.

When bleeding the air out of the new fluid - make sure you crack the banjo bolt at the top as air tends to stay here. Also - overnight - pull the brake lever in, and tie it there and leave the bike on an angle so that the Master R is the highest point in the brake system - this will push most of the air to the Master R over night through the pressure in the system.

[Posh Tourer :P]

I didn't end up checking the valve clearances because the cover had one of those rtv silicone gaskets and it wasn't going to come off without damaging the gasket, and since I don't really know what the clearances are supposed to be, or how to adjust them (from what I've read, I'm guessing it's going to need shims to adjust them), I thought I'd better restrain my curiosity and leave it alone...

They should (in my sum of experience) be a threaded shaft with a locknut to alter the gap between tappet and valve spring at fully open valve. You *need* to know how to get the crank in the right place in the cycle, how much clearance inlet and outlet (outlet is normally larger), and in your case also the gasket :S I wouldnt bother unless you can hear some rattle consistent all the way up the rev range. Also, if you do adjust, dont, whatever you do, adjust too tight ie not enough clearance. It sounds very nice and smooth, but is screwing up your engine as the valves arent opening fully

Changing the brake fluid, I was surprised how many bubbles came out of the front brake system. Does anyone know how they could've got in there? I haven't had the brakes apart or messed with them at all until now. I do remember thinking the front brake started to feel a bit funny half way through a trip from Auckland to Leigh and back, but I'm not sure if I was imagining things, or if that's when the problem started.
Anyway, with the new brake fluid, it's slightly better. It still feels like the brake lever comes in a fair way, but the brake does feel more solid.
I bled the brakes, like it suggested in a bike maintenance book, by pumping the lever and holding it, then releasing the bleed nipple/valve thing and watching for bubbles in the tube, and then repeating, all while making sure the reservoir is topped up. But the only bubbles I noticed came out when I was first changing the brake fluid. Anyway, I guess it's ok.

Your brakes auto adjust, they rely on the pads being physically pushed off the discs to get clearance. The issue of long lag period in the lever should then get better with time as high spots wear off discs and pads. Also make sure your pads are relatively free to move in and out, the beemer had issues with the pins they hang on not being lubed, so the pads were stuck out a bitfrom the disc, hence lever initally only moed this pad closer to the disc and not actually braking. The initial lag in the lever is building up pressure in the fluid necessary to do the braking. Water and air compress a lot hence the sponginess when they are present. Stiffer brake lines will help in this problem also, or better "gearing" ie a different master cylinder (note this is not fluid reservoir - that is different) will allow different amounts of fluid to be pushed for the same amount of effort on the lever. As for the bubbles, they may have come from a low brake fluid reservoir sucking air in? or a split in your lines (unlikely, as you can still brake). No other ideas on that one, maybe someone just did a really bad job of bleeding last time. Also, bubbles can form in the bleed valve cos you are not pushing out enough fluid to fill the valve? so the bubbles may not be in the lines, but appear as the fluid is released...

Thats my load of informed (??) waffle, hope it helps...

[merv]

They should (in my sum of experience) be a threaded shaft with a locknut to alter the gap between tappet and valve spring at fully open valve. You *need* to know how to get the crank in the right place in the cycle, how much clearance inlet and outlet (outlet is normally larger

You've been around the old air heads too long, and for clearance you meant with the valve fully closed eh! Most overhead twin cam engines these days have bucket followers direct on the cams with shims to set the spacing. The old screw adjust type went out with rockers.

[marty]

hey my old CX500b had screw adjustable tappets. easiest things to work on they were, heads off in about 4 minutes, cleaned and put back on in another 10

[Posh Tourer :P]

Fair enough... I suspected that something had changed.... that would also explain why its harder to get in, cos not everyone wants to any more.
Yes indeed, closed... I couldnt quite remember, so I had a 50/50 stab without reasoning it out

[merv]

hey my old CX500b had screw adjustable tappets. easiest things to work on they were, heads off in about 4 minutes, cleaned and put back on in another 10

Yeah you were lucky with those they weren't even overhead cam and were in fact a pushrod engine. Made good power for a pushrod all the same.

[White trash]

I wouldn't use Dot 5 - it is more hydroscopic and needs to be changed more often apparently. I don't think ANY manufacturer recommends DOT 5

Sorry Wkid, but the higher the DOT rating the less hydroscopic. Harley and Buell both use this but a lower rating means it has a higher boiling point, more hydroscopic, needs changing more regularly. DOT5 is also Silicone based so doesn't damage paint. A BIG plus on an HD!

[RiderInBlack]

Sorry Wkid, but the higher the DOT rating the less hydroscopic. Harley and Buell both use this but a lower rating means it has a higher boiling point, more hydroscopic, needs changing more regularly. DOT5 is also Silicone based so doesn't damage paint. A BIG plus on an HD!

Thanks for that, WT . Nice to know I got something right here (with my meger DIY home mec knoweledge ).

The 100% coolant thing is a bad habit I picked-up from a more "exprienced" biker. I'll stop following his bad habits, and let logic, reasoning & knoweledge do the thinking for me. 50/50 from here on in