Engine parts that fit Xbr500

[guest1640]

Hi all
Subject xbr500 engine upgrade to 600cc
Bike xbr500 1986 Australian model without kickstarter.
From what read and other research the barrel from xl600 with the 589 case stamp on it fits with machining cases and changing conrods or gudgeon pins. Add an extra gasket at the base and avoid starter problems from high compression
I would like to have the kick starter as a back up and possibly remove the starter for weight issues, as it will end up a project cafe.  Have started collecting parts and now have a XR600 on offer for low price and will be good for some parts lime a lighter fly wheel and clucht baskets and the like.
Main question does the xr barrel fit without mods?If not what mods would I need:ie: cases machined, piston shaved, conrod exchange etc.
Need to keep xbr cases for registration.
Any input much appreciated. Project on the back burner. Divorce is a bummer...
Stu Aussie xbr fan...

[guest1640]

Typo....
Corrected...
From what read and other research the barrel from xl600 with the 589 case stamp on it fits WITHOUT machining cases and changing conrods or gudgeon pins. Add an extra gasket at the base and avoid starter problems from high compression.
Stu

[JOOLZ]

Correct, 589 barrel and an XL conrod and piston and thats it. The only cases that need machining are from very early model XBR's

[guest1640]

Thanks for the input Joolz. Good to see someone with yr knowledge willing to share. Thanks mate.
XR600 Engine is still in bike and going cheap for $200 au. Minus carb and exhaust. Do the side covers for cases fit and does the rocker box(diesel mechanic) fit the head or am I best to source a XL top tappet cover? Aussie xbr models didn't come with kick starter, hence no decompression lever/cable on the cover...

Have read that the xl600 cdi unit enhance a spark. Bike I have is needing a stator, so I thought I might upgrade. Any info appreciated. Cdi and stator combo? Will eventually rmove battery for weight... Road registered bike...
Any exhaust tips for a two into one exhaust system also appreciated as it's still got to get me to work on any given day the sun is out. He he most of the year here.
Oh and can I have the shirt off yr back. Just kidding. Thanks for yr help...
Come n ride sometime...
Tyresforbikes.com.au
Stu

[JOOLZ]

Yes the rocker cover will fit ok, the right had clutch casing will fit but the alternator cover wont as the crank is longer in the XBR

[blew]

My xbr has an XL 600 barrel and piston and two base gaskets.The compression is HIGH.With hindsight,I would have fitted three gaskets.The electric start cannot turn the engine over when cold,but will occasionally turn it over slowly when hot.I always use the kickstart.Out of curiosity I've tried bump starting it downhill in third,and the back wheel stopped dead.I suggest you fit a kickstart and a decompressor.

[guest1640]

Thanks guys. This bike is going to be bitsa from all over.... Kick start shaft n gears from Germany, kick starter from UK, barrel xl600 from central Queensland,flywheel, covers and rocker cover from sunshine coast QLD, piston n rings from USA and the list goes on.

Trying to upload a pic from my phone but it's not working. Think I need a hammer...

Blew you've got me thinking about cutting out a spacer plate that I can paint.

Joolz is there any other heads that the xbr cam will fit? Xl600, xr600
If so. I'm thinking the combustion chamber might be larger and might not need so many base gaskets.
Have been quoted $450au for a cam grind and hard facing. Seems fair...
Slowly getting all the bits together for a build.. Sadly I don't think I'll be tacking it until summer. Least I can ride the stock bike in the mean time.

Stu

[Propellor]

Hi.

Sounds like you're having fun!

Does anyone readily know the compression ratio you end up with just using one gasket? And what is the engine capacity? Anyone ever done a dyno run?

Cheers.

[Propellor]

Hang on. My last post might sound daft.

I've been comparing specs  of xbr500 and xl600 and the site I looked on gave the bore and stroke as 75x100 for the xl600. Is that the wrong way around?

[guest564]

With 11.6:1 compression my starter would work reliably except first thing in the morning when I needed to use a boost battery.

The bore and stroke is 100 x 75 for an Xl600R, its most definitely a short stroke engine.

[guest1640]

Yer fun watching my bank balance get smaller. Thinking it will be worth it though. Love riding it stock, so I can't wait for a bit extra umph in the back wheel. Recently my stator has failed and trudging through posts found a few comments about fitting the xl600 cdi but not much on generators.
Hoping someone on here can enlighten me on getting a bit more poke out of the spark. It's seems like a weak spark but that could normal. And if there's an aftermarket stator that fits.
Not much knowledge on the cafe set up with smaller batteries and the like. So any info appreciated.
Undecided on carb set up. Thinking the kehien 40 or 42 flat might do but it's seems there's a leaning toward the minkuni. Any thought on that please...

Cheers
Stu

[guest295]

It may be that your alternator can be repaired. The wire coming out of the coil often breaks due to vibration. A very careful soldering job will fix it, but must be covered with shrink tube. As far as I know, the spark gets stronger as the engine gets going, since it's driven straight off an alternator coil.

[blew]

One wire on my xbr stator wasn't working.I tracked it down to a bad soldered joint on the stator itself.All 14.5 volts are there now.Yippee.

[Propellor]

?...........The bore and stroke is 100 x 75 for an Xl600R, its most definitely a short stroke engine.

Ah. That explains my confusion. I've double checked and the site in question definitely had it the other way around. It was only when I realised the xbr500 stroke is 75mm that I realised they might have it wrong.

Which brings me back to a question I was going to ask before I was sent off on a tangent....

When you guys say the compression is phenomenal when doing the xl600 conversion, are you leaving the xbr500 head on?

[blew]

I used the 500 head on my bike.