Building a bike that the mods will wish they had

[BENSPEN]

Hey guys, I'm attempting to get a machine shop to resurface my cylinder head, bmw does not provide the spec about the max surface you can take off. Anyone have any experience with this?

[Laitch]

Hey guys, I'm attempting to get a machine shop to resurface my cylinder head, bmw does not provide the spec about the max surface you can take off. Anyone have any experience with this?

Why does the head need machining?

[BENSPEN]

Couple small knicks, and some head gasket material

[Laitch]

Couple small knicks, and some head gasket material

How about posting some photos of these nicks, Ben, and their relationship to the sealing surface as a whole?

[Martin]

Old head gasket material can be carefully scraped off, small nicks can be removed again carefully with a flat fine wet stone and kerosene. The important thing is that the head is not warped. To check you will need a straight edge  run it the full length of the head and check for gaps. Then run it diagonally from both sides and check for gaps, use a feeler gauge to measure the gaps. It is also important to remove and replace head bolts in the correct sequence and use a torque wrench.
Regards Martin.

[BENSPEN]

well, Im back. I have been working on the bike a lot, but I have not been documenting it. The last you guys heard from me is the head nicks and my resurfacing of the head. I took about half a thousandth off the head, and it looks good, I also re-lapped the valves, replaced the valve seals, and pressed the valves in, but I was missing a lower valve spring retainer, i instantly ordered one off the fiche, and it got here 20 days later, and they sent me an upper valve spring retainer :( I called in a rage and they expedited one from Germany, im waiting on it right now and if its wrong im going to freak out. I got the speedo in my headlight bucket, and the headlight in. My circuitboard from rbm will be here soon and then ill wire everything. I painted my valve and crankcase covers along with my timing chain cover and my inter-cooler myself in gloss black with white pinstripes. I am having a painter do my tank and rims. I am also sending my turbo to XSboost so they can machine out my compressor housing and fit a new compressor wheel and turbine shaft along with a rebuild kit. I serviced my wastegate yesterday and got it really clean, also painted some rubberized undercoat on the headers to protect them. All thats left is to wire, reinstall turbo and head, and make a cafe seat. Pics below.


If anyone has a spare lower valve spring retainer, please let me know if you woild be willing to sell and expedite it to me. I should have asked here earlier.

Thanks and sorry for the delays.
-Ben

I think Don already said that in post #67, Ben, but I suppose it bears repeating. :giggles  In fact, I think you and he have the same style turbos.  :mbird

Just read this, I read #67 and i dont think he said anything turbo codes.

[BENSPEN]

Pics

[Martin]

Rubberized coating on exhaust headers won't it burn off? :dunno

[BENSPEN]

Pics
Wastegate before

[BENSPEN]

Painting


Btw, splines look great!


And ugh, Martin I'm so dumb sometimes! Thanks for the point-out

[nods]

Painting


Btw, splines look great!


And ugh, Martin I'm so dumb sometimes! Thanks for the point-out

Looking good mate. How did you do the white BMW and pin stripe? Do you finish painting it all black, then mask everything off, then paint the white over the top of the black paint?

And are you using rattle cans?

Cheers,
Nods

Sent from my SM-G925I using Tapatalk

[BENSPEN]

Looking good mate. How did you do the white BMW and pin stripe? Do you finish painting it all black, then mask everything off, then paint the white over the top of the black paint?

And are you using rattle cans?

Cheers,
Nods

Sent from my SM-G925I using Tapatalk

Thanks! Means a lot, I was afraid I'd get a lot of "shuld have kept it original".


I am airbrushing, on this I used white primer and activator, then masked and sprayed gloss black with activator and hardener at 8-1-2. I masked with painters tape and a razor blade, painful process, could have used better tape, came out pretty good! So the white showing is actually primer.

[nods]

Nice one I reckon it looks great. Did you blast the covers to prep them or sand them?

Sent from my SM-G925I using Tapatalk

[BENSPEN]

I soda blasted them, then finished with some 400 wetland and cleaned, got about 85% of the paint off but what was left was a good base. The stock paint is so tough I'd say you only would have to scuff and clean to get a good paint. Also used some bondo to fill some holes. Thanks again for the optimism on my project.

[Martin]

I found a local medical supply place that sells surgical scalpel blades in different styles. Really sharp and I do mean really really sharp they are great for cutting the tape around  the letters etc. They fit into one of my craft knife handles. I just went for a ride down there and picked up ten at 60c each, they are old old stock and they now only have one box left. I also found that they had those really long cotton wipe sticks with really huge ends so I bought their remaining stock of 100 they have had them since 2005.
Regards Martin.

[BENSPEN]

I found a local medical supply place that sells surgical scalpel blades in different styles. Really sharp and I do mean really really sharp they are great for cutting the tape around  the letters etc. They fit into one of my craft knife handles. I just went for a ride down there and picked up ten at 60c each, they are old old stock and they now only have one box left. I also found that they had those really long cotton wipe sticks with really huge ends so I bought their remaining stock of 100 they have had them since 2005.
Regards Martin.

Would have made the job 1000x easier.

[BENSPEN]

So, I finally got the German part today!! I was in talking my head and cams and when it came time to do the valve timing, I was running into issues with the chain tension and the marks. First of all, the notches in the cam go straight up right? The Clymer makes it confusing. My issue is when I line them up and try to make the chain tight on top, I then make it tight on the bottom and it moves, very aggravating!! Any advice greatly appreciated, thanks.




Also where does this washer go in the lower cam chain tensioner? Thanks again. Sorry about this!


-Ben

[BENSPEN]

Washer

[BAMBAM1039]

painting the inner cooler is counter productive to its purpose by putting so much paint on it it cannot transfer heat properly effectively killing its charge cooling ability  light coat of flat black or leaving it alone isthe most efficient pretty intercooler equals lost horsepower

[jc55]

This is a cool project. I'm curious about how the white will look...I'm sure it's going to be stunning.


You know about 3m fine line tape? It's about the right width.


Nice work...wish I had a turbo! :riding:

[jc55]

Oh, duh the white was the primer...nice paint work.

[Laitch]

First of all, the notches in the cam go straight up right?

If what you intended to ask was if the notches in the sprockets align with the joint between the head and crankcase and are pointing toward the intake side of the head, the answer is yes. If you are asking something else, I don't know the answer. Have you tried putting a wrench on the camshaft flats when you're tightening down things with your third hand?

If only I could have had a digital camera that I could have used to make images of assemblies before takedown that were instantaneously available when I was reassembling engines 50 years ago. Polaroid film was too costly. :giggles
Maybe you'll get one.  Anyway, that washer looks like it might be the one that is under the clip that holds down the tensioner on its post. The perspective is slightly skewed.

[TrueAce]

Brilliant, Laitch! :clap:

[The Mighty Gryphon]

Washer

Sometimes the parts fiche can give you a hint:

[BENSPEN]

Wow guys love the feedback so much, jc55 thanks so much!


Laitch and gryphon, thanks guys really helped me I was so stressed it was hard to function.


Laitch thanks for the write up helped me a lot when I was timing it! Ive got it all timed up now, I aligned the notches in the cams with the seam between the head and the camshaft retainers. Looks correct in my Hayes manual, does that seem right?


Thanks for the pic gryphon, washer fit well there, and for the description laitch.


I'm constatlntly impressed by the instant advice that comes from you guys at such a quick rate.


So, ive got one last question which brought my progress to a screeching halt tonight, how does one preload the cam chain tensioner? How tight should it be? I feel like my spring is doing nothing, only the preload? My Clymer says nothing! Thanks guys this one really puzzled me and my coworkers who know nothing about bmws. Thanks, and I'm so sorry about how many questions I've asked rather than documenting my progress, "Ben's technical q and a thread"


Finally, BAMBAM


Depends on how you do it, intelligently or not, as long as you only paint the very surface of the cooling fins you affect the actual raw aluminum surface area by probably less than a percent. Also, if you mask the fins until the final coat like I did, you barely add width to the fins, only slightly affecting the airflow. Yes, you are correct though, it likely robs horsepower, but, personally I'd rather eat one less taco tonight and regain that power in power/weight.




Thanks guys!