Bonneville America Forums Forums Technical Forums Performance Mods Weisco Big-Bore Cometh

BT's great pic above confirms that the crank is a cast one. (Look at the "parting line" running from the crank pin up towards the main bearing - see that is it rounded, and not ground on, as a forged crank would be.)

As for a stroker "kit", Falicone cranks emailed me that they can do a welded stroker on your Bonny crank. Even though it is a cast crank, an expert welder should have no problem building up the botton side of the rod journal (probably with an intended-for-cast-iron nickel alloy arc rod).

To make it easy to get the proper piston, just get a set of custom Carillos which are shorter by half of the increased stroke. In other words, if you stroke it by 10mms, get a rod that is shorter by 5mms. Then you can use the stock piston pin location (known as "compression height").

Wow, an 1140cc Bonny motor! South Bay must be using their machined-from-a-solid-chunk barrels along with a stroker crank. Sounds good to me!

Don't forgings have parting lines too?

But at any rate, that is a great pic!! Heckuva lot more exposed than I will ever see on my bike! (hopefully...)

AS THE CRANK TURNS (episode 56):

I found the friggin magnet! But my wife doesn't care about that, - she's just glad I "scoured the floor of the garage" (Pat, she sends her thanks for your prodding).
Anyway, here's a pic of the little SOB below.



Also, the pic up above that shows the split case is actually not my motor. It is Jojje's motor ( the "Turbo Swede" ). In fact, you'll notice that the picture shows a crank that has a 360 degree firing sequence (the connecting rods line up parallel with each other), whereas the TBA's & Speedmasters have a 90 degree delay between pistons (a 270 degree firing sequence).

After all of this, I think I'd enjoy that "stroker kit." Maybe by next winter it'll be available.

Stay tuned,

-BT

As my bud Ted would say, "Most excellent dood!"
Now get backl to work putting it together.

Matt called me last night and wants me to start his big bore project tonight. I guess I'm gonna have to haul all my stuff over the his garage now. He better not have that swill beer he always buys. I think I'll locktite my magnet onto the end of the telescoping thingy too, don't want to go through your headache.

Well,

Now I got to do that U.S. Army thing (you know, "hurry-up and wait"). I went to I-90 Motorsports, my Triumph dealer (who rarely has what I need), and ordered various & sundry gaskets, and they didn't have most of them in-stock. They did provide the clutch-cover gasket, so I put that together.

Also, Mike Auderer (the owner of AMI Racing Engines) thoroughly inspected my valves and he really wants to do a 5-angle valve job (along with porting, polishing, & matching the manifolds with the intake ports). He said, "yeah, it'll run you a few dollars more , but I would be much happier with it (It'll be like the SB head below).



So, now I wait. I was going to get that belt-drive & FCR Carbs, - but not now as my budgeted money is running low (perhaps in the Spring). That's okay, I want to see what that Weisco kit feels like when I goose it with the 16T primary sprocket .

Perhaps I'll spend my time cleaning my greasy frame up and taking a few pieces in for powder-coating.

So, this "manly soap opera" may have a string of boring episodes.

-BT

Good idea to clean up the frame! Tie up some loose wiring, etc. Who knows, you may find some chipped paint under there that you can touch up, prevent some rust! Looking forward to the next episode...

bennybmn,

This whole thing is really getting my juices flowing (I used to rebuild VW Bugs & a Karmann Ghia). I'm beginning to think about getting an old, rebuildable, Karmann Ghia and creating a masterpiece (see pic below).



But, first things first.

-BT

Phil,

Sorry. Didn't mean to "piston" you off.The magnet was stuck to my footpeg, shifter, foot-brake mounting crossbar thing-a-ma-bob.

-BT

Dude a rebuilt Ghia would be sweet. My grandfather had one of the first bugs here in the states, then my dad got one, ended up selling it when he went into the army, and bought another one in Germany when he was stationed there and shipped it home! Too bad I never got to see it... I love those things. Barely fit in one, but they are cool! I think building a dune buggy would be fun too...

OK sorry for the thread derailment!!

bennybmn,

Since now I gotta wait, - yet working on this thing has gotton under my skin, I decided to take on this little side project.

After all, As The Crank Turns may be having re-runs for the next few days.

-BT

Yes, Benny, forged cranks have parting, or forging lines. These lines are ground down after the crank is stamped, which leaves the distinct look of grind marks, as opposed to the non-ground casting mold parting line.

Also, the surface of the cast crank is different from that of a forged crank, in that it is more like an orange peel, whereas the forging is slightly smoother.

Forged cranks were the norm in older bikes and older Detroit cars, especially HP engines, since they were almost always stronger.

But, Pontiac used cast steel cranks for some years, and Ford used nodular iron cast cranks in many HP motors, and both of these are really tough items.

Aftermarket crank makers (like Crower) have made cranks out of large steel billets. (I've seen Crower's crank milling machine in action and it's impressive how it roughs out the basic unit.)

Remember that forged cranks used to be made in a couple of forging stampings: first a flat mode, and then a twisting of 90* on each end of a V-8 crank, while the center section was held fixed. These twisted forgings were not at optimum strength where the twisting was done, BUT, later, advanced techniques were developed to where the manufacturer could do a NON-twisted forged V-8 crank, where the metal grain was not stressed.

Many bike cranks have been built-up ones, made of several pieces pressed together, in both single and multi-cylinder versions. This is easier for an engine manufacturer to build, as they don't need a dedicated crank grinding machine.

There's lots more to be said about car and bike cranks (and radial aircraft engines with a master con rod and slave rods), but that would be hijacking this great thread even worse. Anyone interested in really neat bike cranks can go here to learn more: http://www.faliconcranks.com/

I see what you mean Papa. Hard to see the surface in that pic... Saw some interesting radial motors and the Glen Curtis museum up near Pat's at the Noreaster! Really cool stuff.

I'd definitly like to see someone do a stroker for our bikes! Just one more chapter in the power saga...

John,

The new aftermarket cams that came were the wrong cams. The ones that came fit the Bonneville T100. Since the T100 has a 360 degree firing sequence, they don't work on my Speedy. I'm glad I noticed the shipping label. I was told I would be in receipt of the right ones by Monday or Tuesday. What that will mean is that I 'll be installing the re-newed motor over the long 4-day weekend.

You probably noticed that I started powdercoating some things. Well, Monday I'm going to take my swing-arm in for powdercoating. After that, I think that's all the powdercoating I'll do until after I start it up and get it Dyno-tested.

Anyway, below is my Speedy.



So, what do ya think?

-BT

You've got kajones that clank man.... I can't say I'd take on all that. Glad someone else went before me!

I think.... I could keep up if we went for a ride, tomorrow. Nice! It's going to be a piece of art and speed. I hope you placed all the fasteners in a dish somewhere. Now I have to get back to thinking.

So BT, how you gonna break it in? Easy or hard?
I did mine hard and have had zero problems with it, never a leak or nuthin.
Also, hold off on the dyno until you get it nice and broken in, at least 500 miles. And you will also need to use standard dino oil, no synthetic until many miles. I waited until over 4k miles before going back to synthetic. That way I was sure it was nice and sealed on the rings. Besides, it ran just fine with the other oil anyway. Standard 10-40w. I also changed the initial oil out after 50 miles to get rid of any initial metal particulate. Then again at 250, 500, 1000 and 3000.
Come on, git er dun! Matt and I are on schedule to beat you to the punch at this point.

Pat,

My plans are to install the motor on the long Thanksgiving day weekend. But, with the complete head/valve grind job I'm getting done, and the stage one cams, I think my valve clearence readings (on diassembly) are now worthless. So, I anticipate having to dink with that until they're set right.

Also, I removed my swingarm for powder coating last night, and it looks like I gotta go get those damned bearings pressed out before I get that done.

So, four things give you they upperhand on finishing sooner.

1. I'm a lazy SOB
2. You've done this before, and therefore have less miscues.
3. I have a longer list of items to attend to (I'm in deep, dood).
4. There is two of you, and just one of me.

All & all, it's still great fun though. And, I started this on Oct. 23rd, so it still less than a month.

-BT

Pat,

As for breakin, - AMI Racing engines is strongly urging me to let them break the motor in at their shop. It's some fancy procedure they have on their dyno-machine.

I'm considering it.

-BT

Sounds like a good plan to have AMI do the break-in for you.
Keeps ya covered, unless of course you have to sign the "If we break it, you pay to fix it" clause that every dyno guy I have seen makes me sign before hooking it up.

Quote:

---

4. There is two of you, and just one of me.

---

Yea, but it's Matt , so it takes even longer if he helps. I have him do the simple stuff as I drink, then I let him fetch me fresh beers when there's real work to be done.

Pat,

I haven't met Matt, but it sounds to me like you better make him the "designated driver" .

I dropped the swingarm off to have the bearings pressed out. My machinist (Tim) said that sometimes that seal (in the picture below) gets damaged when removed. But, I want the thing powder coated, - so I'm marching on.

LEFT-SIDE SWING ARM BEARINGS





RIGHT-SIDE SWINGARM BEARING (a needle bearing)




-BT

AS THE CRANK TURNS (Weds the 23rd)

Well, it's been one month since I started. At this point, I've put the motor back together (lined up & synchronized the crank shaft marks with the new aftermarket "stage 1 cams." But, the shallow side of the new cams are ground much thinner than the stock cams. This will require much thicker shims. I calculate about 3.10mm (the stock ones were mostly 2.85mm). So, as a result, I'm not going to get those thicker shims until Saturday morning (AMI Racing Engines are getting them for me).

So, grrrrr, - I'm stuck waiting again.

Stay tuned,

-BT

Hey BT,

I enjoy reading this thread. Thanks for taking the extra effort to keep us all in the know! So you'll have some shims for our informal shim bank?

AS THE CRANK TURNS (Saturday the 26th)

Finally got the proper shims and all the clearences are close to perfect. So, the pic below shows the motor I've alway wanted for my Triumph (problem is, it's not "in" my Triumph, - yet).





The next pic shows the polished exhaust ports.





Then, after a couple hours, here a pic of the new hot motor mounted in my Speedy.





Now I'm wondering about if the stock bottom-end can take all the new top-end muscle (904cc, porting & polishing, five-angle valve job, & stage 1 cams).

It's still going to be a long, cold winter ahead, - so I'll be patient.

-BT

Daamn good article. If you are feeling depressed after you get it together because you can't ride it that much in Washington, I will gladly ship it down here for you and all us Floridians can ride it around for you and tell you what we think.

Great post.

Looks great so far BT. hope it goes back together easily for you. I bet that's gonna be one scootin motorscooter now eh?
I just got the call last night that the machine work is all done for Matt's, so we gotta get it all back together this week sometime. Just in time for the snow, got 6" the other day.

Today's Report (the 27th)

I calculated the cost of this whole thing, and because of the "Stage 1 cams" and also the decision to get the "QPD Beltdrive" (along with everything else, like extra powdercoating & extensive valve/headwork), - I'm up over $3K! OUCH! I guess it's cheaper than buying a new rig.

The pictures below show my progress today.




I decided to go back to the 160 main-jets.




I also put an extra needle-shim on each needle.




I also did the 7/64th vacuum-hole enlargement.




I neglected to post a picture of the new smoother intake, so here it is.




This picture shows where I'm at now.


Stay tuned.

-BT

I did some wiring tonight, as well as checked various torque specifications.

I also studied the difference of the shape of the lobes on the aftermarket cams compared to the stock ones (see pic below).



-BT

Excellent pics BikerThug, by chance, did your new cam come with lift / duration / lobe center specs, and / or timing diagram?? Excellent thread, keep it going!

November 30th

Well, there is really a sense of light at the end of the tunnel. I believe I'll be starting up this coming weekend.

The pics below show where I'm at today.



Since I am now more familiar with my Speedy (from reassembling it) I must say I do not like the little plastic "fir-tree" buttons that hold up this starter cable as well as the hydraulic-line from the foot brake. I'm thinkng about doing something different.



I polished and mounted those proud Bonnie pipes tonight. I think I'll be starting it this weekend.

Stay tuned,

-BT

PS - If anybody can think of something I forgot, by all means speak up.

All those little tree push-in wire holders suck. Especially the one right below the carbs where my oil gauge is. Always comming out... Let me know what you find for alternatives!!

Hey BT, run Braided stainless steel brake line instead of the factory line. I'm trashing the Triumph set up alltogether and using an aftermarket setup from Pro One,Accutronic, or Hurst.

angelis745,

Take a close look, I've already put them on (I bought them from Brent about a year ago).

AS THE CRANK TURNS (Dec 1st episode)

Tonight I installed the newly powder-coated swing-arm. Since the QPD beltdrive is on back order, I re-installed the chain (after thoroughly cleaning it). Also spent a lot of time this evening checking & rechecking many torque specifications.

(See pics below)


This is what my Speedy looked like one week ago.



This is where I'm at tonight.

We're getting there.

-BT

..aah-hem, while buttoning things up, I trust you have that magnetized retrieval tool safely stored away somewhere clearly identified. Not that I don't trust your obvious mechanical skills

JH

Way to go BT it looks great. Your doing one hell of a job there.

Gotta give ya one thing, she sure is clean and shiny!

Looks great BT. Wish I could hear you fire her up that first time. Have fun.

wojo,

You will my friend. Success or failure, I'm going to give a link to an .mov file of me starting it for the first time (or trying to start it, - we'll see). It'll be one of those "thrill of victory" or "agony of defeat" kind of .mov files.

DEC. 2ND REPORT

Finished off all the routing for wires, breather tubes, etc. Installed the metal battery holder, ignition swith, & remounted the fuse-box better than stock. Cleaned, then recharged my K&N filters with that funky red filter oil. Started trickle charging the battery.

Here's another interesting little tid-bit, - not a single part is unaccounted for (nuts, bolts, washers, plastic fasteners, nothing). That's a first for me.

So, I'm cautiously optimistic.

Here's a few pictures of tonight's progress.






Stay tuned,

-BT