FZR400 winter overhaul | Page 8 | GTAMotorcycle.com

FZR400 winter overhaul

Wicked buddy. Turned out awesome. All the work paid off.
 
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:wav:
 
Beauty! Can't wait to see it in person.
 
I suppose I should update this. The bike has been running very well. The general feel is like that of a new bike, which is what I wanted. With a couple of suspension adjustments, the steering is near perfect. I slid the forks up through the triple clamps a few millimeters and took about half a turn of preload out of the shock, that's it. The steering is neutral and practically effortless, but stable. It is hard to imagine a better-steering street bike than a stock FZR400 ... but it is. About the only criticism for street riding is that the ride is pretty harsh. At some point I may swap out the 20-weight fork oil for 10-weight.

1000 km since rebuild (break-in for new piston rings) passed last Thursday, at which point I changed the oil filter and put in Amsoil 10w40 synthetic oil. There was nothing scary on either the magnetic drain plug or in the oil that was drained out. Oil consumption appears to be nil.

Earlier in this thread I mentioned that I had raised the needles in the carburetors by one clip position to solve a cold-engine driveability issue. That was too much. Fuel consumption increased (was around 4.5 L/100 km, now it's low 5's) and I'm told the exhaust smells rich when riding, and today's ride in warmer weather revealed some rich chugging down at the bottom of the rev range. So, tonight's chore was to put the clips on the needles back where they were but with the washer underneath the clip, which basically puts it halfway between where it was last year, and where it's been this year up until now. Haven't ridden it yet with this adjustment. Having the airbox off also allowed confirming that there is no longer a coolant leak at the thermostat housing.

The cylinder head work - smaller intake ports - greatly improved mid-range (above 4000 rpm - below that is where it feels too rich). It's now actually possible to overtake cars without downshifting three times. It's no ZX10R, but it does actually accelerate below 10,000 rpm.

Keeping an eye on the battery water level is a chore that I don't miss ...

There is still a to-do list, but it's all minor (and will likely wait until next winter).

Something that I completely forgot about last year is that both backlighting bulbs in the speedo are burned out. Can't see the speedo at night. The bulbs are probably $2. Taking apart the upper fairing completely in order to get to those bulbs ... can wait.

There is something machined slightly out of tolerance in the spacer between the front wheel bearings. If you clamp up the axle, the bearings go tight. For now, it's put together without the axle tightened (so that the bearings are not preloaded) but locked in place with the pinch bolt; it's not going anywhere so it's not really an issue. Fixing this requires disassembling the front wheel due to the captive spacers. That can wait, too. The way it is now will work, it just requires not following standard procedure for installing a front wheel.

And, I don't like the cush-drives that these (and most other) aftermarket wheels use. They are FAR too hard, and provide negligible cushioning. I can't help but think that this contributed to the transmission failure that I had with my race bike last year. I have concocted my own cush-drive bushings out of a steel washer and a combination of 4 rubber O-rings in each of the 6 drive pins, in place of the very hard urethane donuts that the wheels shipped with. This provides roughly the same cushioning (going by feel) as the stock cush-drive in the stock rear wheel, BUT, those O-rings don't last. (Fortunately, they're cheap.) What's really needed is to fabricate new urethane bushings that are roughly 70 shore A in hardness (much softer than what the wheels shipped with), but that's likely also a winter project.
 
The cylinder head work - smaller intake ports - greatly improved mid-range (above 4000 rpm - below that is where it feels too rich). It's now actually possible to overtake cars without downshifting three times. It's no ZX10R, but it does actually accelerate below 10,000 rpm.

When you get a chance, send me some details on the intake size changes - been thinking about going that route on the motor I'm building for next year.

There is something machined slightly out of tolerance in the spacer between the front wheel bearings. If you clamp up the axle, the bearings go tight. For now, it's put together without the axle tightened (so that the bearings are not preloaded) but locked in place with the pinch bolt; it's not going anywhere so it's not really an issue. Fixing this requires disassembling the front wheel due to the captive spacers. That can wait, too. The way it is now will work, it just requires not following standard procedure for installing a front wheel.

Let me know how this pans out also. One of mine has a similar issue with the stock wheel and spacers - been trying to figure out a solution. Any thoughts?
 
When you get a chance, send me some details on the intake size changes - been thinking about going that route on the motor I'm building for next year.

Post #66 in this thread goes through the math, and post #69 has a link to more information on how to do it (you will have to dig through a lot of other stuff, but it's in there).

Let me know how this pans out also. One of mine has a similar issue with the stock wheel and spacers - been trying to figure out a solution. Any thoughts?

Pop one of the wheel bearings out (you will need to replace it with a new one) and either make up a shim or have a new bearing spacer made up which is a fraction longer.
 
Post #66 in this thread goes through the math, and post #69 has a link to more information on how to do it (you will have to dig through a lot of other stuff, but it's in there).

I knew I should have re-read the thread - lazy me, there it is.

Pop one of the wheel bearings out (you will need to replace it with a new one) and either make up a shim or have a new bearing spacer made up which is a fraction longer.

*sigh* was hoping that wasn't it. But I knew it was. So much for avoiding another bearing pull. ;)
 
Near-end-of-season update. All is well. The only mod since the start of the season was a set of Advmonster LED headlamps to replace the very weak 35-watt OEM bulbs. http://stores.advmonster.com/h4-led-headlight/

I had the bike to Deals Gap the week before last, and put 1500 km on it down there. Today I did an oil change. 70,875 km on the odometer total, which is about 4600 km since overhaul.
 
Long time no update. Had a minor malfunction tonight :( At a gas station when I turned the key on and pressed the starter button, no start - no crank. Nothing. Everything else electrical was working, so I bump started it (easy to do on a small-displacement engine) and got home to investigate further.

Upon pressing the start button, the lamp check for the oil level warning comes on and the headlight goes off ... which means the starter button itself is working. But there is no click, which means the starter motor is not working because the relay is not pulling in. Looking at the wiring diagram, the problem has to be either the starter relay not pulling in despite getting power, or the interlock relay not pulling in despite getting power. The interlock relay is built into a relay module that includes some other stuff including the turn signal flasher circuit, which has also been acting up for some time ... erratic flashing rate; I considered this to be a minor nuisance not worth investigation, but it looks like that has changed.

I suspect the problem is either inside the relay module or with the wiring to it. For the moment I'm going to jumper the appropriate terminals on the plug to the relay module and see if the engine starts with it like that - if it does, then it's time to open the "no user serviceable parts inside" relay module and find out what makes it tick, or find another relay module.
 
Same thing had happened to me. It was the relay on one of my 400s. Got a hairline crack in it and water got in making a mess.
 
Update: Fixed! To check the starter solenoid, you are supposed to unplug the control wire leading to it, which has a single bullet connector in it, and connect it to ground using a temporary wire, and see if the starter motor operates. Well, I found the problem before I even got that far. Evidently when I put the bike together, I didn't get that bullet connector plugged in far enough, because it was unplugged! The detour through Caledon on Monday's ride, which sent me over a washboard gravel road, is probably what shook it loose.

I did take the opportunity to swap the relay module with a spare, and coat the connector with dielectric grease before plugging it back in.
 
Update. Winter storage. 78,029 km total, 11,760 since rebuild. The only thing done lately was to clean the brake calipers and flush the brake fluid.
 
Long time no update. 83,514 km total - it hasn't been getting much annual mileage. I've been a little unhappy with the harshness of the front suspension on our choppy and frost-heaved roads ever since I built this (see post 149 above), but not unhappy enough to do something about it, until now. Today's rainy-day job:
- Re-grease and snug up the steering head bearings
- Reset the emulator (compression-damping valve) to 1.5 turns of preload on the spring, about one turn less. This essentially backs off high-speed compression damping.
- Change the fork oil. It stunk. I put in 10w this time, which should take a little damping out all around. I also lowered the level about 10mm.
- New brake pads (also cleaned up the calipers while installing them).
- Fresh brake fluid.

-
 

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