3xv: Project Phoenix

[Steveog]

Following up on Marin's thought, "that these problems can often be good fortune", I'll share one more "look-back" at the recent build that was a pain in the ass, but could have been much worse.

This re-build was only going to be the cylinders, pistons and heads. However, after mounting the pistons and about to install the cylinders, I rotated the crank with the flywheel and there was an occasional drag and hanging-up on the otherwise smooth rotation. After checking further, I could hear an occasional screeching sound. Oh Shit. There was only one thing to do. Pull the crank. I consulted M77 in a PM and he predicted it was a bearing. I was praying for a piece of piston wedged into the web run. But, I'd already blown a lot of air through the crank cavity. I had also coated the crank with some thick petroleum grease, hoping to pick-up any loose metal. No evidence of broken pieces.  If the center bearing was harboring a piece of schmutz, the crank would have to be rebuilt. "No more fun of any kind."

Well, Martin was right. But, fortunately the 2T gods were with me on this one. I found a tiny piece of metal wedged into the outer LH bearing race and removed it with a mechanic's pick. If I had proceeded to start the engine with that tiny piece still in the bearing, things could have gone bad quickly. Having the crank out also gave me a chance to cleanup the areas of burnt oil and thoroughly clean, blow-dry and properly lube up the crank and check all the oil journals in the cases. Peace of mind.

That crank was new with only about 5-6 hours of use in anger. All tolerance/specs were good to go. The rods' upper ends looked good.

I'm going to the Shop to install the engine, RH Carb, then build out the throttle cables.

Good day to all.

Steve

[Martin77]

Having experienced the pleasures of a broken engine on a few occasions, you learn debris can get everywhere..hence thinking there was some bits in the bearing.

[Steveog]

Thanks, again for your instincts, Martin. The sharing of experiences on this Forum is perhaps its greatest asset for guys like me. Hoping there's someone who can benefit from my story. Someone once made the analogy, "that a 2T is much like an exotic animal. Requiring special care and feeding. Even then, it might not want to be tamed." 

The hang-ups and metal-on-metal scraping sounds were intermittent. The crank would rotate free for 10 revs, then catch or scrape. After it stopped completely, I called in the the specialist and pulled the crank.

Good day in the shop. The engine is mounted and some work done on the magneto, flywheel and the cooling system. The new primary radiator hose is 1" in diameter. Its in two pieces to custom fit the TZR coolant impeller housing to the dual-core TZ radiator, which are different OD's. I heat-bonded a piece of PVC to the stock housing. It matches the new hose to spec. Out of pure paranoid, OCD, I plan to safety wire the new silicone hose clamp to two of the hex-heads on the impeller cover. I'm not sure why the hose failed on 8/16, but it will not fail again.

I didn't bother trying to clean up the shop for a wide shot of the bike. Those cracks in the floor are probably due to coal mine-blasting, but they've been there for 15 years.

Its amazing how much easier mounting the engine was this time.

Time for a cold one. Thanks again, Martin...and to all who have offered help.

Steve

[Martin77]

My only minor concern with the water pump exit pvc tube, is if it has a straight surface without a little ridge, it might be a bit 'smooth' for the hose to grip onto. I guess it's tapered a bit which will help hold it?

Good day's work though!

Soon be time for testing again

[Steveog]

Yes. Good point, Martin. The PVC does flange out a bit. It was heated to fit. The hose material gets good traction on the PVC.

The alternative is to over-tighten the hose to the stock piece. That's why I chose to use safety wire on the clamp to be sure.

Testing soon. Hoping for a start-up no later than Tuesday. Building out the throttle cable is the only "job" I'm facing. The rest is paint by the numbers.

Thanks for keeping an eye on me.

Steve

[Steveog]

Got the lower carb fully modded for idle control. The spot that was intended to mount an idle adjustment screw was cracked-off when I got the bike, so this mod has seen some evolution. It works in practice (with no engine vacuum). If this doesn't work with the engine running, I'm screwed (literally) as I don't have time or money for a new carb at the moment and a track day is scheduled for the 28th.

I thought this would be my last engineering before assembly and testing, but the lower exhaust flange cracked at its mounting point. I could bodge up a fix that would work, but I ordered some stuff called "Alumaloy". >https://www.alumaloy.com/<  If you don't care to look at the the site, its a rod that can weld aluminum, but doesn't require anything except a propane torch. Its low-temp stuff, relatively speaking. Much like solder, but it "becomes aluminum".

My exhaust flange is unique to my pipes, I believe. They only match DFR units. Yamaha flanges are NLA. Yes, I have a tech who welds aluminum, but he's a bit unrelaible and I can't deal with his vague deadlines. Shopping around for such specialty work will take more time than its likely to yield good results.   

The demos and comments about this Alumoly seem positive, but I'm wondering if any here have used this stuff. Your reviews would most appreciated, as I can start work on my "shade tree" solution if this stuff is bogus. It only cost me $10 for 5 X 1/16inch rods. I'll have it Friday.

Thank to all.

Steve

[Steveog]

Well, now I know how tricky building out a one-into-two cable can be. I used a Vinton Kit. Its far more simple and much lighter than the diabolical stock version. It works and the carbs are sync'd, but the action is stiff. Lubing it properly would seem to be the solution. HA. Here's a video of the throttle working and what the details look like. Not very exciting, but part of the story.

Looking forward to the "Alumaloy" getting here tomorrow. I showed the break in the exhaust flange to large industrial shop that built our transport. They were dubious about welding that specific aluminum casting on a part that would be very hard to fix otherwise.

Thanks

Steve

[ybk]

My DFR's flange also snapped off the bit where the bolt tightens. Previous owner probably overtightened as it actually bent up a bit. I had it welded up and 'filled in' then just filed and sanded it all down to the original size and shape.

Nice one with the throttle

[Steveog]

Thanks, Karel. Yes, the other side of the same flange looks slightly stressed (bent a bit), too. I can't blame anyone other than myself for it braking, though.

Wondering if a thick, high-temp O-Ring acting as a washer behind the flange wouldn't save this expensive part from unnecessary stress. Place the O-Ring over stud, supporting the flange. Might give the flange some needed help as opposed to just air.

The industrial guys I spoke with are good, but not motorcycle specialists. As I said, my "bike" man is just not reliable...although talented.

If this "Alumoly" doesn't work, I've got some aluminum stock standing by to build up a way to tighten the flange and still make this last Track Day. It won't be pretty, but will seal the pipe to the exhaust port.

I really appreciate your support for fixing this crucial piece of kit.

As we go into fall/winter, hope your spring/summer treats you well.

Steve

PS - Concerning the throttle. Hard to believe I had a 45 year career in video production. After fiddling with the throttle mechanism most of the day, I just bodged up the video. HA. Regardless. Kind words: Good.

[Warwick]

Good to have that cable sorted, eh? What's the reason for making it so long? (I can;t quite see from the pics, but I'm assuming the upper cyl carb cable must loop right round the engine bay?

[Steveog]

Yes, Warwick having this cable in place is a noticable improvement. Much better now that its properly lubed. HA. The quick-turn throttle I modded up works as I had hoped. Even with the higher ratio the overall pull is lighter than the original.

Your observation is spot on. I chose that cable length to allow more options when snaking around rear carb air box. I've also installed some large, in-line fuel filters for each carb. This meant a new piece of fuel line. Just wanted to make it all fit with minimum hassle. I will have the whole winter to tweak and clean-up the entire engine compartment. Still too many wires, too.

I tried that Alumaloy rod on the broken exhaust flange. I got it to melt but, obviously the cast aluminum of the flange, just didn't get hot enough. It needs to be properly welded. Another winter project for my heli-arc guy. In the mean time, what do you think of this solution?

I cut a template of the flange that is about 1mm thinner than the portion that holds the exhaust gasket. Obviously, I need to drill out the holes for the studs, but it seems that the big chunk of flange would hold the gasket in place and the smaller piece would be anchored by the template. Using the spring mount on the right, would allow adding safety wire to hold the big section to the right hand stud, holding the gasket square and get me through the last track day. It also saves any further destruction of the pieces of flange.

Sound OK, or is it hard to visualize? I know its probably the most outrageous "shade tree" idea I've yet proposed, but I'm stuck. Still need to change the tyres, run-in an almost all new engine, test and tune the bike all in one week. Any opinions/options would be greatly appreciated.

Thanks for your looking in on me.

Have a good weekend.

Steve

[maccas]

Steve,

Are you saying that you have the copper gaskets fitted in the cylinders?

If so, that is why you have cracked the flanges. They are designed to fit straight into the cylinders with the gasket removed. You seal them with a bead of high temp silicone!

I'll get a picture for you tomorrow.

Dan

[Steveog]

Thanks, Dan. No. I'm using pattern gaskets from CrusinImage.

I believe I broke the flange after I installed a new stud in the lower cylinder. I did not take the time to rotate the bike...attempting to apply a "snug-up" of the flange by reaching under the cylinder. I heard a crack, but was shocked to discover the flange had broken.

I used these same exhaust gaskets with RTV on the original re-build. All good. They held up well, even when the bike "heat-seized" in mid-August.

If I'm wrong, I honor your expertise. Any help is appreciated.

Steve

[maccas]

You shouldn't be using an exhaust gasket at all with those flanges. The flange should sit flush against the exhaust exit from the cylinder. I'll send a pic across tomorrow.

Dan

[Steveog]

I'll look forward to seeing what you've got. The bike came with thin copper gaskets. () The pattern gaskets were about twice as thick.

This time things need to be done properly. I get what you're saying about using RTV as opposed to ANY/NO gasket. The Expansion Chamber has an O-ring groove to seat into the flange-mount for proper sealing. New, Hi-Temp O-Rings, standing by. I've been using RTV mounting the pipe to the flange, too.

Yes. No wonder the flange broke. They were under unneeded stress this whole f'ing time. I had no idea. The DFR site is not very helpful on this subject.

What's your opinion of my one day "fix"? I'm guessing proceed using the RTV, but lose the template AND the gasket. Tighten down with safety wire is the question.

Thanks again.

Steve