Bmw r75/5 microsquirt project for a newbie

[R100RT]

That is not the crank from your engine. I believe I may have been wrong on it being a ball bearing style (for the main journals) and would be like the image below.

IMG_1510.JPG

That is supported by bushings pressed into the case, and the front carrier, with thrust rings at rear for end float (much like my vintage then). As you can see, the counterweights get in the way, but this model is much easier to work on/ remove from the one piece crankcase, if an overhaul is being considered. I would take a close look at the surface condition of the connecting rod journals through the removed cylinder mount holes, clean with brake clean and snap some photos for us to consider.
As well (and sorry for delay this morning - couldn't get out of the work shop ) but I am posting over on the ADV forum on your behalf, for a parts search. I will try to send you a private message to further discuss in a few moments.
Lorne

[R100RT]

The post is up over on ADV, can be found here
http://advrider.com/index.php?threads/7 ... p.1207371/
I see about sending you a PM,
Lorne

[R100RT]

Jeremey, hoping to have some further feedback from you on crankshaft condition?
Can you take any photos, can you advise if the journals show any bluing, can you run a finger nail over the surface and feel ridges, or slide smoothly. Some deposits and material wiping may adhere a surface that can be polished out, so don't jump to conclusions.
Lorne

Starting to get some response to this over on ADV, so need to share on the crankshaft condition

[fefenin]

Thank you so much Lorne ! I also find an eBay seller located in the Bronx. An r100 engine case with all I need but he won't send it to France . I will still ask. That is probably an r100 /6 or 7 that will fit my cylinder and piston. And it is not so expensive

Envoyé de mon U FEEL LITE en utilisant Tapatalk

[R100RT]

So, I am advised that a crank from any Airhead boxer will fit your /5 crankcase. The front journal on /6 and later crank is smaller and hence would require the bearing carrier plate, as well the rod bearings can differ. But if you scored a late model case with rods on the crank that would be a good approach. Also, your flywheel might have slightly smaller dia metric fasteners, there were 10mm, and 11mm used but the flywheel material drills easily so that can be modified. But, don't get too far ahead of things - what is the condition of your crankshaft? (PS - had a gentleman from up Alaska way offer an engine, that is really too far )

[Tennesseejed]

I gotta hand it to you Lorene, you are a relentlessly helpful person.

Good on ya mate.

I'm still following this thread to see how fefenin's project develops. And at the moment it appears to be on the rev limiter in reverse. Hopefully he can source parts locally and get back on track.

[fefenin]

It is nearly impossible to find parts locally. I am actually trying to deal for the shipment of a full lower r100/7 engine from NYC. I could also get it from Canada that would do. I am back in reverse but will come back soon hopefully.after thousands euro spends probably. Thank you so much for the help anyways

Envoyé de mon U FEEL LITE en utilisant Tapatalk

[Tennesseejed]

My friend here in Alaska has two R100GS crank assemblies, but even if they fit in your chassis (I don't think they do) it would cost a fortune to get one to France.

Is shipping a R100/7 from NYC really less expensive than obtaining a crank, bearings and have the machine work done locally?

However it turns out, I'm rooting for ya.

[R100RT]

Jeremey - still waiting to hear what your crank looks like?

[fefenin]

Sorry guy I am stuck with no proper tool to remove the fly wheel, only thing I need to remove the crank. Waiting for a shock tool thingy ( would appreciate to learn the name ) and then I can tell you. I think it is busted cause I see grooves from the bearing . But maybe I am still within the tolerance . How to now for sure.

Envoyé de mon U FEEL LITE en utilisant Tapatalk

[fefenin]

And in the meantime I am waiting for the guy to answer so I know if sending an engine from USA is worth it or not ...

Envoyé de mon U FEEL LITE en utilisant Tapatalk

[fefenin]

Used Crankshaft on ebay.fr is the price of the full r100/7 in NYC without piston cylinders and heads

Envoyé de mon U FEEL LITE en utilisant Tapatalk

[R100RT]

If you can see groves on the rod journals of the old crank then generally speaking it isn't worth the time/money to restore.
Seeing as how you may buy a complete block with crank, are you looking to just mount up your Pistons, jugs, and heads without a swap over? Either way there are constraints:
a) the R100/7 I believe needs a full review to confirm compatability of a number of areas ( jug mount dia, stud size, many other things)
b) removal and reinstallation of a crank is technical and a full inspection of case bearings and oiling system flush is critical .
Which way you leaning. Also, there may be more parts options via ADV, one R75/5 short block is available up North of British Columbia - the fellow PM'd me

[R100RT]

Sorry guy I am stuck with no proper tool to remove the fly wheel, only thing I need to remove the crank. Waiting for a shock tool thingy ( would appreciate to learn the name ) and then I can tell you. I think it is busted cause I see grooves from the bearing . But maybe I am still within the tolerance . How to now for sure.

Envoyé de mon U FEEL LITE en utilisant Tapatalk

Not quite sure I understand the question - perhaps you refer to "An Impact Gun"? There are many ways to "skin the cat" as the saying goes (& that is rather gross isn't it )
To remove a flywheel without any special tools I would do this:
a) block the crank from turning by jamming a stud of wood through one side of the crankcase to wedge the rod journal as she rotates - can't really hurt it now.
b) If the clutch assembly jumping out as the fasteners are backed off is a concern, just remove one and match for longer threads to control the plate.
c) use the best 6 point socket and extension with a T bare or strong ratchet - add a cheater pipe to extend the leverage and get a mate to hold the block while you loosen fasteners. Support under the extension so that it can't twist off the bolt.
D) bolts aren't that tight - should come loose easily.
e) flywheel should wiggle off crank without problems, if that's stuck then heat Center with propane torch while wacking outer surfaces.

[fefenin]

Ok I'll try that but I have no proper 17 spinner ( wrench) .
I'll buy that and an extractor this afternoon. Thanks this is very detailed.

Now there is no timing chain no clutch so everything is ready but the bolt are quite tight and the only 17 spinner I got is busted. Don't want to break more things.


And yes it an impact gun seams very logical

I'll tell you what happens next

Envoyé de mon U FEEL LITE en utilisant Tapatalk

[R100RT]

Hi Jed, good to hear from you - I'll send you a PM to avoid the displeasure and discipline of the site administrators.

Jeremey, I've requested a price from the gentleman up in Ketchikan, Alaska with R75/5 short block (that's somewhat near Jed ), shipping would of course be something to recon with but if you aren't finding anything on your continent then importing is probably required.
Regards,

Lorne

[fefenin]

Damage... Cannot extract the camshaft screw

Envoyé de mon U FEEL LITE en utilisant Tapatalk

[R100RT]

Stuff like that happens - I find its helpful to spank the end of the fastener smartly in between attempts at extraction. What sort of head or drive pattern was on the fastener? Allen head, slotted, or?
Also, once things have gone badly, use a chisel to take nips at the removal direction from each side if possible.
If none of that works, then cut or drill the head off as you will be able to remove the remaining threaded stud from the block once things are out of the way and new fasteners are sourced.

I still don't see real definitive damage for the crank - can you add a photo looking in through from each side of the jug mounts? (like a dog with a bone - just can't let go of that one).
The oil pumps are robust and oil delivery is way over supplied so can sustain a bit of carnage there and still be okay. Of course, cleaning and close measurements and such is always required for a quality job.

[fefenin]

Thanks again for all your efforts . Here is your bone
This is Allen key hole tapered screw . I hope I can drill and then remove it. But I will try soldering a nut on to first

Envoyé de mon U FEEL LITE en utilisant Tapatalk

[R100RT]

That photo of the rod journal is not convincingly bad. Any way you can get a close up with your phone set to macro image? If it isn't bad you might have an option to rebuild your stuff. As Jed has mentioned in a PM, there is a need to determine the root cause of this damage though.