Planning a 570 rebuild

Hi all,

So I probably have one of the 70-degree bikes that encounter premature big-end failure. The signs so far are metal sludge + thin metal fragments in the oil screen. Plus a knocking/cattering sound.

At this stage I there are some gaps in my knowledge about tools, and what parts to replace.

I'm reasonably handy and have a decent mechanical intuition, but I'm pretty green in the motor rebuilding department. I'll have some of the finest advisors on the project I could possibly have ...

First is my grandfather who was a Citroën mechanic in the '50s/'60s, specially trained in the crazy French hydraulics they used to have in Citroën cars. He used to align crankshafts by hand with copper mallets and built his own valve cutting gear out of scrap. Great, great man. Always willing to help everybody and share what he knows. I'll be working in his aircraft hangar, next to the airplane he built - a 215kg two-seater with motor modifications, and aluminium wing tanks he welded himself. 215kg for an entire airplane, meters long and meters of wingspan! And I thought 'Bergs were light! It's like a crazy bird skeleton or steel spiderweb, wrapped tauuuu-ut in doped nylon canvas. The construction is fascinating, and then you can climb into it and fly in the air to boot. So good. I'll be sure to post some pics of it.

And then secondly I'll get some great help from some local experts who have graciously offered to drop by and help me figure things out, at least if I can scrounge up a cup of decent coffee for 'em.

And then you guys

I'm going to try to do everything myself except for pressing/aligning the crank. Will take this to a well-respected local privateer mechanic.

I have a basic set of tools - most wrenches/heads you'd need and some decent torque wrenches that cover 6-200 Nm or so. Impact screwdriver, old-school calipers, feeler gauge.

I'm going to get a dead blow hammer and a magnet-on-a-stick. I'll need a chain tool for the cam chain, right? Or doesn't it need to come apart? I'm fairly sure I'll be able to borrow a flywheel puller.

Should I get a case splitter, like these ones from Tusk or Motion Pro?
A crank puller/installer?
A clutch hub holder?
Micrometer?
Digital calipers?
Dial indicator ("clock")?

And then I'd really appreciate some pointers about what parts we can KNOW beforehand I'll need to replace. Do I need a full gasket set? Or just a headgasket?

Let's assume that the rod and big-end bearing need replacement for sure. Will the debris have trashed things like main bearings and oil pumps? Should parts like this be replaced on principle, or can they be checked and verified as bad or good? The bike hasn't been ridden much, only 46 hours on the clock. So these items probably won't be worn from standard use, only from having bearing trash forced through them.

I am looking forward to the task, and want to take it slow, select good parts, and build a reliable motor. I really love this bike and want to do this right ... but I am a little cash-shy so I have to save where I reasonably can I'd prefer to investigate and learn and check things carefully if it means I can save on parts.

So that was the wall of text. Thank you for reading

Hey dude, sound like the skills knowledge and location are all locked down.

Mains, go to speed supplies.com, search for KTM 690 bearings. They were half the price of genuine parts here in Australia, alternatively NJ207ECP can be sourced from a supplier.

Pro X lists a big end bearing and pin.

A KTM 530 rod may fit (not 100 % sure ) But then you need to use a piston with a 18mm pin bore.

Have a look in the sandbox, from memory wossner or elko makes a piston to fit the 550 that will go in the 570 (100mm) but the pin bores are 19mm so the 570 rod would be required.

Gaskets, you cant go past cometic, get a hybrid head gasket and the MLS base gasket. At 48 hrs, I would reuse the clutch and flywheel cover gaskets if they come off without tearing. As a little bit of insurance I would replace the crank oil seal, simple generic oil seal. I got one that was 7mm thick and surfaced it down to 6mm on 320 emery over a thick sheet of glass.

You need a dial indicator to measure end float of your crank, set this up to the biggest clearance even as big as 0.5mm. Or pray that the float somehow magically happens to be correct when the crank is assembled. Do not be tempted to leave it tight. Have the crank pin welded if you plan to beat the hell out of the motor.

An inside mic to measure the cylinder if you're using file back rings, Ive used a digital vernier with good results.

The cases and crank come apart/out very easily due to the cylinder rollers. There are also ears cast in the case to make the initial case separation easy.

Oil pump, yes replace it, it just a matter of course after a bottom end failure.

Chain breaker not required for the cam chain.

THANKS!

That really really helps connect the dots. Gives good traction for further reading. I've learned a ton from threads here, not least your rebuild thread mr. Smerg ... really appreciate you helping push my enthusiastic but feeble self across the threshold here

I read between the lines that it is simply the rule to change the main bearings in this situation?

No worrries mate !

Yes you did read between the lines correctly my friend

You'll be right mate, git-r-done !



sent from the side of another mountain in the PNG highlands via a dodgy satellite link.

PNG bergsmlerg ? lookout dude

they lace the kava with high grade crack, you'll be grafting a busa front end onto your 610 with a hand scraper in no time.

KD its the 628 04 up "650" elko piston or equivalent that could fit, as far as the interwebs go there is only one post on this forum somewhere from one bloke who tried it in reverse ... 570 piston in the 628.

would love to see some pics of that airplane

Thanks bushie, I knew one of them could be a candidate, researching the net is a little bit difficult here. Not my first rodeo up here, and crack laced kava would hit the spot right now but its a dry cramp, and the rules are enforced by guys with well used Mosberg pump guns

Sorry about the thread jack tourist but at least you got a little more info.

berglsmerg said:

Thanks bushie, I knew one of them could be a candidate, researching the net is a little bit difficult here. Not my first rodeo up here, and crack laced kava would hit the spot right now but its a dry cramp, and the rules are enforced by guys with well used Mosberg pump guns

Sorry about the thread jack tourist but at least you got a little more info.

Click to expand...

haha, you owed me one remember

Re. parts - I was thinking to go with OEM as much as possible. I'm not sure but the word seems to be that it's generally the most reliable stuff.

Cometic gaskets though as you suggested, and then I'm wondering about the conrod ... Does anyone else have a hunch that the OEM 70-degree rods are a bit varying in quality? Have seen posts that the frayed big end looks unusual. Might be better to go with a nice Carillo rod or similar?

Carillo yes yes yes ! Order one now because the lead times are horrendous.

Then you can source a pin from pro-x and a peek coated big end M profile bearing from the suppliers that spanner found. The oem b.e. bearing is a flat profile which does not help the big end roller track at all.


http://www.twostrokeshop.com/peek_coate ... earing.htm

Ok thanks for letting me off the hook on the threadjack, It wont happen again :unsure:

So silent here without the threadjacks Bring 'em on!

But yeah, I'm having a little financial "oopsie" ... turns out the apartment I was renting is a taa-ad moldy so I need to divert all my extra money into a new place to live ... arrgh ...

Considering whether to sell the DR-Z to pay for 'Berg repairs ... but I can hardly bring myself to do it. Had my mind set on playing some tricks on the motor and suspension to bring out the best in it: Raise compression w/ E-type offroad model base gasket, KLR650 carb + jet kit, maybe cams, DIY suspension revalve, maybe cutting the springs a bit as I'm close to being the right weight for them. The work itself ought to be a lot of fun - and the DR-Z is said to benefit A LOT from these mods. Low-hanging performance fruit. The Zook also has such a nice setup already - a very nice French titanium full exhaust system from CRD - sounds a bit like a Ducati down low and a '60s racecar up high (!) - but still pretty quiet. Then there's a brutal homewelded skidplate from last owner, huge handmade bar risers etc. - it's way more off-road ready than a standard DR-Z ... and these goodies wouldn't really fetch a fair price so I'd always be eating a loss if I sold it, at least in how I feel about it.

Also makes it less appetizing to sell the Zook that it's time for a valve adjusment a few other maintenance tasks to get a decent price for it. As in I'd have to spend time and money and dedication just to be able to get rid of it and not be burning myself on the sale, kind of.

The 'Berg is a bit of a luxury animal; conversely, it's so nice with the DR-Z to have a bike that you're willing to put through dirt and salt and asphalt miles without a worry or a care. So I'm going to go to some extra measures to not have to sell the Zook. But it's going to SUCK having the 'Berg lying half-disassembled during the summer - riding season is already starting!

*vent*

I know you'll understand - thank you for reading! Thanks for being there for a bro :crybaby:

Aww dude that sucks. I feel your pain there well and truly. My berg was dismantled for 9 months, during the dry season over here. Very temperate climates and no monsoonal rain, perfect riding. But it was worth the wait.

I filled in the time chasing my son on his KTM 50 sx mini with a pit bike and a lil zook DS80 that I restored, at least I got some bike time in.

Just give the DRZ some tough love, save your cash for the berg my friend, stay positive, while you wait for parts port the head, match port the throttle body and the spigot, check the wiring harness for rubbing spots. Pull all the chassis bearings, clean and repack them with quality grease, factory greasing is notoriously sparse. Spend some time on those maintenance items now so you will just ride when you build the motor.

hmm good thinking!! thanks for that ... transforms the berg from a sad reminder to a PROJECT again!

Hmmmm. Things are looking less gloomy - and I am sounding less whiny ... Just sold my beautiful 12-string Seagull guitar - for approximately the cost of an OEM conrod kit. That has to have some kind of meaning, right?

It is better to have loved and lost than to never have loved at all ?

I know a bloke who knows at thing or two about guitars.

Hit up Travis at thumper racing, he will hooked me up with an after market rod kit at a attractive price.

Yes project not dead bike that's the spirit !!!!

Haven't found the Cometic base/head gaskets for sale online so I contacted them directly - that's the way to go, yeah? thx!

Try looking for the ktm equivalent eg 530 exc

The hg will be 100 mm bore still ktm though

ahh I see! many thanks!!

Finally ordered the gaskets! ... had some problems with the Cometic site, it seems like it didn't work with my non-US credit card? Although it's supposed to work with some billing address magic that the card company does. Sort of by accident I googled the gasket part number "C3244-EST" and found a couple of hits on Amazon by chance ... got the complete top end kit for $48.12 shipped! It's $61.31 excluding shipping on Cometic's shopengineparts.com site. The full kit includes head, base, exhaust gaskets, valve stem seals, cam chain tensioner O-ring and crush seal, and rocker arm O-ring. Nice!

Comes from Amazon shop "ehgoods" which are these guys afaik: Lion Parts Store

100mm bore or GTFO!

I've placed an obscure coin there for a convenient size reference

shipito.com is really nice! thank ye O mechanic of bushes

I contacted carillo about a week ago for info on a rod they said it takes 12-14 weeks to make to order so It would be about 4 months to get it in belgium I guess..

Hello Tom,



This would be a custom connecting rod application that we can produce in 12-14 weeks and the cost per rod would be $378.50. This connecting rod would be stronger and last as long or longer than your stock connecting rod. You would have to purchase this connecting rod from one of our distributors. In Belgium our main distributor would be Greenspeed and you can reach Jean or Nicolas at 32-23-582-919. If you have any other questions please feel free to contact me at any time.



Best regards,