1971 Triumph Bonneville Restoration: Front Fork Rebuild

It's all snow and wind outside so I spent a good six hours in the garage this weekend rebuilding the front forks and the triple tree on the '71 Bonneville winter project.

The forks on the bike had been 'choppered' with massive fork tubes and spacers in them.  The bike came with new stock fork tubes so after a cleanup both front forks got rebuilt with stock fork tubes.  I'll put the chopper ones up for sale and see if it'll make a dent in the new parts order I got in.

The internals on the forks were in good shape (it has always been stored inside).  After a cleanup they went back together again nicely.  The picture on the right gives you an idea of just how long those fork tubes were (almost as long as the whole shock!).

The right side front fork went right back in no problem, but  the left side one won't fit in the lower triple tree mount (it has a bolt that squeezes it on but the circular clamp is too tight.  I've tried heating it up and wedging a screwdriver in the gap to respread it enough to accept a fork.  I shouldn't complain, this is the only thing that's being difficult on this fifty year old machine so far.

The lower fork unit as it came out of the giant chopper tubes.

The same piece cleaned up.

Parts diagram from the '71 Triumph's parts manual.

Meanwhile, the first parts order came in from British Cycle Parts.  They were great helping me clarify what I needed to get started.  The order was about $450 including shipping and got here quickly (within a week), one box from their Canadian warehouse and the other from their U.S. one.  I haven't started installing anything yet, but I now have what I need to rebuild the Amal carbs, sort out the electrical system and take apart the motor to prep it to run for the first time.

Motor gasket set!

Electronic ignition system and coils!

Amal carburetor rebuild kits!

Rubber bits!  This time 'round I got a new kickstart rubber & the gear shift rubber.

That's a stock style new rubber to replace whatever the f*** was on it.

The monkey who was choppering the bike put massive footpegs on the rear peg position,
but that doesn't make any sense on a chopper (they're usually feet up and forward).
These are the stock footrests.

Stock foot rests (and hardware)!

The plan is to rebuild the carbs, get the motor sorted, install the upgraded ignition system (which I suspect will also involve creating a new electrical loom) and then see if I can get it all to run.  Once I've got it a step closer to running I'll be back in touch with BritCycle to get the other bits and pieces I need to get it rideable.  The plan is still to get it to a place of getting a safety and putting it on the road next season.

I'm not a big fan of lost causes and I wrench to ride, so the point is to get the Bonneville back into service. After watching a lot of Henry Cole on TV, I like the idea of a 'rat bike', which also means I can focus on the mechanics rather than how it looks.  If I can get the mechanics sorted to the point where I can ride it, I'll do a season with it rough but rideable and then consider my options.  I got the bike and spares for $1500 and I've just put another $450 into it.  I think I can get it roadworthy for under $4000 and a non-running barn find bike of similar era was going for a grand more than that a few weeks ago online, so no matter what the Bonnie project won't ever drip red.

In a perfect world I'll get it sorted and some one will offer me more than I've put into it (cost, not time, I'm happy to put time in keeping bikes on the road).  Whether that's once it's roadworthy or once it's been cleaned up too, I'm easy.  Meanwhile the Bonneville is doing what I wanted it to:  giving me an opportunity to go deep on a motorcycle restoration and learn a lot in the process.

The motor's getting cleaned up and recommissioned.

Once the (now stock) forks are back in I'll wheel it out for a deep clean on the motor
and then start with the electrics before rebuilding the carbs.  With any luck the old Bonnie
will be to the point of starting by the new year.

Somewhere in between all this deep surgery, the Concours needs new brake pads and the Tiger has some new sprockets and a chain to install.  To be honest, these minor maintenance jobs are something to look forward to after the deep diving into the restoration project.

Last winter was a deep maintenance round on the Tiger, but even that pales in comparison to the scale and scope of the Bonneville restoration.  Practical Sportsbikes and Classic Bike are both magazines focused on hands-on motorcycle mechanics and both have talked about the dreaded project stallout that can happen when it all gets too much.  I'm taking the advice of both mags and breaking this up into chunks and then solving things subsystem by subsystem.  The small wins help me feel like like the project is progressing and prevent the dreaded project-stallout from being overwhelmed by the whole thing.

On the upside, the fact that we got 15cm of snow over the weekend isn't really on my mind as I'm keeping track of many things-to-do in the garage.

Triumph Tiger 955i Engine Remapping

There are a number of posts on this blog about working out the kinks in my 2003 Triumph Tiger 955i,

and this is another one.  I've been playing with the Tuneboy engine management software that came with the bike, which works well, is put together well and is easy to use.  In working with the Tuneboy kit I discovered TUNEECU, a more open-source option for programming your own engine maps.

If you've never wrapped your head around engine maps, they're not very complicated.  Tuneboy does a good job of explaining how it works in their primer that comes with their software.

Back in the day you had a carburetor that used screws and jets to set the amount of fuel that got metered into the engine.   If you changed altitude you had to start swapping hard parts (usually the jets that sprayed fuel) to keep the bike running right, and sooner than later you had to manually trim the whole thing to keep it running right.  Electronic fuel injection took that all away.  A computer under the passenger seat on the Tiger takes inputs from sensors in the air-box (barometric pressure), in each of the three injectors , the fuel pump, radiator (engine temperature) and a crankcase sensor to constantly adjust things to use the most effective amount of fuel to make the bike go.  Put another way, carburetors are a mechanical, low resolution solution to feeding fuel into an engine.  Electronic fuel injection is a responsive, high resolution fix to the problem of delivering the right amount of fuel to a motor.

Tuneboy map editor - you can change settings and tell
the ECU (electronic control unit) what to do under
certain circumstances.

A fuel map is a spreadsheet of numbers.  Sensors feed the computer what RPM the engine is turning at and how much throttle is being asked for and based on the number in the fuel map, the computer delivers a set amount of fuel.  The 'fuel map' is literally a map that directs the computer to deliver a set amount of fuel.  If you're at high RPM and have just shut off the throttle, a smart EFI system will cut fuel delivery entirely, saving both fuel and emissions, something a carb couldn't manage.  If you suddenly give the bike a handful of throttle at low RPM, the map will direct the fuel injectors to deliver an optimal amount of fuel as it picks up speed, whereas a carb will always just send a mechanically set amount of fuel based only on how much wrist you're giving it.

In Tuneboy's system, you can change fueling and ignition maps, and modify things like idle speeds. The issue has been that the only maps I can find for Tuneboy are the stock ones from Triumph, which were set up to favour fuel economy and emissions over smoothness and drive-ability.  Meanwhile, TUNEECU (if you can navigate their 90's style web design and atrocious apostrophe use) offers you modified tunes that can smooth out your lumpy OEM map.

Of special interest to me were custom edits that made the list and have been on there for 9 years.  I don't know who Deano from South Africa/SA_Rider is, but they know their stuff.  The map on there does wonders for your Tiger's smoothness and pickup.  It might use a bit more fuel if you're heavy handed, but the difference in motor operation is impressive and worth it.

I was unable to find a digital tool to transpose the HEX files from TuneECU into my Tuneboy DAT format, so I opened up the modified HEX file and transposed the numbers over to the Default Tuneboy 10120 Triumph engine map and resaved it.  You can find that modified Tuneboy DAT file with the TuneECU South African mode here.

Finding this stuff isn't easy, and it's only getting harder as these old bike recede into the past, so I'm hoping this post help you find what you need to get your Tiger purring again.  It did wonders for mine.

Even though the old vacuum pipes held vacuum, I swapped them out for some similarly sized clear fuel line I had (you can see them going from above each injector to the idle stepper motor.  The TUNEboy software also comes with a diagnostics tool (with very cool 90s graphics!) that lets you test the radiator fan, idle stepper motor (which moves up and down modulating the vacuum in that black thing to the left/bottom in the picture) and the RPM gauge.

LINKS

You can find TUNEboy here:  https://www.tuneboy.com.au/

It comes with a cable that'll connect to your Triumph and is easy to get going, and comes with all the stock tunes.  It also lets you tune on a dyno, if you're minted.  It ain't cheap, but the minted guy who bought my bike new was, so he sprung for it and I'm still enjoying his largess over a decade later.

TuneECU can be found here:  https://www.tuneecu.net/TuneECU_En/links.html  Try to get past the out of control apostrophe use - they're better at software than they are at the speaking English goodly.

The older version is free, but finicky with Windows' old serial port drivers.  You can buy the app on the Android store for fifteen bucks, which seems perfectly reasonable.  You can then connect via bluetooth from a phone or Google tablet, though I understand you miss some connectivity that way.

It gets tricky these days finding the On Board Diagnostics (OBD) serial cable you need to connect the bike to the PC.  You can buy 'em from the UK, where people like fixing things.  CJ Designs in Wisconsin will sort you out with one too:  https://cjdesignsllc.com/?s=TuneECU

The modded engine maps for Triumphs on TuneECU can be found here: https://www.tuneecu.net/Custom_Tune_list.html

The TuneECU page goes into detail about how you might use the TUNEboy cable, but it requires so much messing around with knocking default Windows drivers out of the way and forcing others on that I wouldn't bother (I didn't).

Tiger Brains

The other day I was once again going over the details on the Tiger after taking the tank of for the billionth time.  Even though the stock pipes for the vacuum controlled idle system for the electronic fuel injection hold vacuum when I test them, I can't test that when they're on the bike, so they might be leaking where they join.  I happened to have some fuel line in the right size, so I've taken out the Triumph hoses and put these clear ones on instead to isolate another possible point of failure.

Once I got them in I fired up the TUNEBOY software and figured I'd run the idle control system test since it would move the plunger up and down and with everything off I could check to see that it's all working as it should,  except the ECU wouldn't connect to the computer.  I've done dozens of TUNEBOY adjustments now and know how the bike syncs with the PC over the serial port, but it wasn't connecting.  While trying some variations I turned the ignition on on the bike and the ECU made unfamiliar popping noise, and then none of the dash lights would come on (the running lights still do though).  The ECU no longer clicks off when the ignition is switched off either, which suggests it's not coming on either.

The intermittent nature of this failure always made my ass twitch in terms of it being electronic rather than mechanical.  Mechanical failures tend to be more consistent and easier to diagnose, and I've replaced everything around the idle control system now, so unless Triumph sold me a dickey idle control motor, which seems unlikely since the first one lasted 17 years and did over seventy-six thousand hard, Canadian kilometres and survived seventeen -40°C Canadian winters.  Assuming all the new parts are working as they should, an ECU that was losing the plot is as likely a culprit as anything else I've been chasing, and now it seems to have popped entirely.

So what do you do when your old Triumph's bike brain loses the plot?  Get another, I guess.  Used ones seems to be extraordinarily expensive and look to be in rough shape out of US used parts suppliers on eBay.  And for some reason they're charging twice what European suppliers are for shipping.  With that and the fact that The States seem like they're on the edge of a civil war, I think I'll be looking to the dependable Germans who have COVID19 well managed for a replacement Tiger brain.  If I'm thinking that, I wonder how many other people are avoiding business with the US right now.

But before I go that far, I'm a G.D. computer engineering teacher, so I'm hardly going to let an ECU go in the bin without having a go at it first.  If this is a short or something simple, I can solve that easily enough.  If nothing else I can see how the ECU is set up architecturally, but more often than not I'm able to get electronics I have to open up working again.  Time to flex my soldering prowess.

The most frustrating part about this is that I may well have solved the idle problem with replacement hoses, or maybe I didn't.  Maybe I chased down all of these hoses and parts for nothing and it was the ECU losing the plot all along.  Electronic Fuel Injection (EFI) is a wonderful thing, but the early systems were fragile.  There a lots of posts online about early Triumph EFI headaches, and I've added to them.

Guy Martin does a good special called The Last Flight of the Vulcan Bomber.  They grounded the last of these nuclear bombers in 2015 because they no longer had the expertise and technology too keep them safely air worthy.  In the show Guy talks about why there are plenty of older planes like Spitfires still flying when the Vulcan has to be grounded.  He says the Spitfire was made from bicycle parts you could fabricate in a shed, so they're relatively easy to maintain.  The Vulcan was an industrial machine with early electrical and electronic systems that were many times more complicated.  He goes on to talk about how the Vulcan looked like it came from another planet when only seven years earlier an Avro Lancaster was the state of the art.  There are performance advantages in these leaps forward, but there are also maintenance headaches that mean these early jets will never fly again.

Early fuel injected bikes are a lot like that Vulcan - they can do things earlier bikes can't like get better mileage, not need parts changed to ride at altitude and generally require less maintenance.  I just fixed up one of the last carbureted bikes, a 1997 Honda Fireblade, over the winter.  EFI was around then, but Honda wisely went for highly evolved carburettors rather than new, fragile and poor performing EFI systems.  I rebuilt the carbs, which are a complex but highly evolved four-carb set, and the bike runs like a Swiss (or rather Japanese) watch.  The EFI on the Tiger did the job without any attention for 17 years and seventy-six thousand kilometres including two rides into the Rockies - something no carburetor could do, but when it finally broke, boy did it break.  It's things like this that will make these first generation EFI bikes rare in the future.  Like the Vulcan, they're so complicated and difficult to maintain when they go wrong that they'll get retired from service where an older, simpler bike might still be fixable.



RESOURCES FOR CHASING DOWN ECU PROBLEMS ON A TRIUMPH 955i MOTORBIKE:

https://www.ebay.com/itm/Triumph-Speed-Triple-955-2000-2004-ECU-Steuergerat-CDI-S1000T3/324154967093?hash=item4b79244435:g:BCEAAOSwZrteryUL

There are early Triumph EFI issues aplenty online:
https://www.triumphrat.net/threads/ecu-repair-refurbishing.525873/
https://www.triumphrat.net/threads/bad-ecu-on-my-2006-speed-triple.159082/
https://www.triumphrat.net/threads/955i-idle-hesitation-porblem.971699/#post-2004081361
https://www.triumphrat.net/threads/ecu-unit.80778/
https://www.thetriumphforum.com/threads/s1000t3-ecu.22000/
https://www.triumphrat.net/threads/1999-955i-ecu-needed.93566/#post-1107942

Used Parts, not of the vintage I'm looking for though:
http://www.rubbersideup.com/triumph/tiger?p=2

https://www.bikebandit.com/oem-parts/detail/triumph/t1291000/b1389042?m=121594&sch=565828
Wahay!  A new ECU is two-grand, AMERICAN!  That's over $2500 Canadian!  The whole bike cost me three grand.  See what I mean about the costs of keeping emerging, fragile old tech active?

One Tight, Not Too Tight

Now that the CBR900RR Fireblade project is sorted and on the road, I'm finding myself doing what the original intent was in getting it:  learning from a different type of motorcycle.  Unlike the heavy industry Kawasaki Concours, or the SUV of motorcycling Triumph Tiger, the 'Blade was built to a different design brief. The other bikes were over engineered heavy to last, but the the Honda is a feather.

That philosophy is at odds with the heavy handed git who owned it before me and managed to maintain it into such a state of disrepair that it kept it off the road for years.

From the rear brake cylinder that was assembled backwards and over tightened, to the over tight wheels and the slipping clutch I've just adjusted to actually be at spec rather than over-tightened, I'm finding the Honda was a victim of a heavy hand and unsympathetic mechanical inclination.

When I was a teen my dad was talking me through a head gasket repair on one of my first cars.  We weren't minted, so the only way I was driving was if I could keep an old car on the road; mechanical training was an implicit part of vehicle ownership for me growing up.  As we were tightening the head back on he made a point of talking me through the bolt pattern - always tightening opposite bolts so it would seat evenly, and then said something that I've never forgotten as we started tightening down the head:  "always one tight, not too tight."  I guess the guy who abused this lovely piece of Honda engineering into years in a garage never got such good advice.

Mechanical sympathy is an important part of maintaining any machine, but especially a motorcycle, where if you are cack-handed you can end up seriously hurting yourself when it breaks.  In that way, motorcycle mechanics are a lot like aircraft mechanics, it's a do it right or it can go very wrong kind of situation.

Part of that sympathy is taking the time to understand what the engineers who designed the machine want you to do in terms of looking after it.  In the case of the CBR900RR, Honda would like you to leave 10-20mm of play at the end of the clutch lever - this one was set so you could strum it like a guitar string.  This play is to ensure that the clutch fully disengages when you let go of it.  An over tightened clutch cable means it's always set to be slightly pulling and engaging the clutch.  Making it too tight isn't just a failure of the hands, it's a failure in thinking that wounds the machine.  In this case, the over-tightened clutch cable explains why the 'Blade was slipping RPMs when I opened it up.  A sympathetically tuned motorbike will give you a purity of interaction that allows you to more fully understand the machine.  This is one of the reasons why I value technical fluency so much, it puts your ability to operate technology into focus in a way that the technically ignorant will never realize.

***

Meanwhile, in the land of Tim where he's trying to keep a 17 year old European and a 23 year old Japanese bike rolling during the perilously short Canadian riding season, the Tiger's stalling when hot continues.  I've ordered a replacement air idle control valve from Inglis Cycles, who have once again exceeded expectations during a pandemic by sourcing the part from Triumph in the UK and getting it to me in about a week.

One of the nice things about the Tiger is that it's fuel injected, so all that carburetor management is taken care of, but the evil end of computerized fuel injection is that after seventy six thousand kilometres it's finally gone wrong, and an electronic system like that can go wrong in a lot of different ways. 

I'd never gotten into the Tuneboy Software that came with the Tiger (the original owner installed it along with a Power Commander), because if it ain't broke, don't fix it.  But now that it's broke, I got going on it the other evening.  Getting into the bike via a computer was pretty cool.  The software is Y2K retro-hip and the connection was straightforward.  The 20+ pages of instructions weren't really needed (I'm handy with computers).  Windows 10 automatically recognizes what you're plugging in (back in the day, WinXP would have needed drivers installed), and the software is responsive and quick to connect.  It occasionally drops connection, but unplugging it and plugging it in again resolved that each time.


The compact disk (told ya, Y2K hip!) had all of the stock maps for my year of Triumph Tiger 955i engine on it, so I saved what was on there in case it was some kind of cool specialty map the previous owner had worked out (dude worked at a nuclear power plant, so don't underestimate his tech skillz), and then I flashed it with the stock numbers, which took about 20 seconds and returned a confirmed result.  There is a slight lag, but otherwise this is easy to use stuff.

I then played with the diagnostics tool for a bit, hoping for some data that will help me isolate the hot idle stalling fault.  The software says there are no errors (promising that this is that mechanical failure then), and the only thing that looks out of place is a strange return on the engine temperature.  It seems to read accurately and then show -40, even when the fan is coming on, but if the fan is coming on and the temperature gauge on the dash is reading normally, I suspect this is something to do with how the software syncs with the on board computer rather than an actual fault, but I'm going to keep it in mind.

The problem with an idle fault on a fuel injected bike is that the engine management system is taking in data from a number of sensors and using it to balance engine activity, like idling, based on that information.  I've got the mechanical component that regulates idle on the bike incoming, and I hope that resolves the issue, but what I fear is that it's something else, and with these complex electronics systems could mean that anything from a dozen different sensors or relays to a loose or broken wire.  With any luck, it's that idle air control valve and I'm back on the Tiger... and the Honda, just not at the same time.

Motorcycle Destinations: Mostly Ironheads In Elora, ON.

There was a time when every motorcyclist was also an amateur mechanic.  Getting your hands dirty was the only way to keep early motorcycles running.  We're over a century into the evolution of the motorized bike now and, as in all places, digitization has taken over.  Modern mechanics are now called technicians and have to be as adept at communicating with the computers on a modern motorcycle as the old school types were at diagnosing a mechanical fault with their senses.  Both are complicated, but in quite different ways.  There are obvious advantages to modern bikes in terms of efficiency, ease of use and dependability, but motorcycling is inherently a compromise in convenience, and many of the iconoclasts who escape the clutches of automotive transport to ride in the wind question the replacement of human skill with automated assistance.

Back in the day the motorcyclist themselves performed many of the tasks that a modern day technician does, so what was left to the old school mechanic?  What you'd typically find in a pre-war motorcycle repair shop looked more akin to a machinist's bench than the antiseptic, electronically focused diagnostics bay of a modern day garage.  That ability to manufacturer your own parts and diagnose problems without computer support, using only your senses and your hands might seem simplistic and archaic, but it was nothing of the sort.  There is a secret art to working with pre-electronic, analogue motorcycles that trips up many modern technicians who, while adept in leveraging digital tools to diagnose digital machines and replace parts, struggle to diagnose and repair mechanical faults.

***

If you're into restoring older machinery, this vanishing skill set is hard to come by, but I'm fortunate to live near one of these rare, independent, locally owned shops.  Lloyd Gadd is the owner and operator of Mostly Ironheads in Elora, Ontario.  With decades of experience in mechanics, he approaches motorcycle repair old school.  His shop is part machinists, part mechanics and part historical ode to The Motor Company.  Lloyd focuses on older Harley Davidsons, but as the name of the shop implies, it's not an exclusive focus.  Lloyd is also a qualified mechanic who can do everything from MoT safeties to changing a tire.

I was in there most recently getting last winter's Fireblade project safetied, and in the process Lloyd's prompt service got me looking at a better way to do motorcycle tires that will save me a significant amount of money.  While I was over there I also did a round of photography to give you a sense of what goes on in this old school shop.

Multiple engine rebuilds of air cooled Harley twins were ongoing in this small but dense workspace.

Unlike like most modern shops that simply refuse to work on long term mechanical or machinist driven repairs in favour of high turnover/quick to repair parts replacement, Mostly Ironheads will actually machine parts and rebuild a motor from the ground up.

It's a whole other level of mechanical commitment when you are prepared to turn your own parts out.

Lloyd has a number of customer projects on the go, and also makes a point of collecting older and vintage parts.  If you're fan of Harley Davidson you should make a point of riding up to Elora and checking out what's on hand - in many cases you'll see parts that are so rare that you may never have seen them before, even if you're into classic hogs.

Lloyd told me the story of a 1950s Harley racing motor he'd come across.  Only one of the two heads is accurate, but he's on the lookout for a replacement - though seven decades old serviceable racing parts don't survive well, as you can imagine.  When he has this rare piece of motorcycling history back together it'll be one of the few remaining complete Panhead racing motors in existence.  You might think that's a one off, but not in this shop.  Even if you're not into HD, this place is an ode to moto-mechanical history and worth a stop.  Air cooled bikes have an aeronautical aesthetic to them that modern bikes often miss.

The machining needed to sort this head out is impressive.  It had worn down below spec so is now being built back up and reground to specifications.  When you can machine your own parts, you're as much an engineer as you are a mechanic.

 Being a restorer, Lloyd is always on the lookout for parts, and the shop is an ongoing work in progress, with parts coming in and getting sorted and stored until needed.  Previous customers, online and estate sales and various other connections like the Harley Owners Group mean Mostly Ironheads are able to draw in older parts, often found in boxes of 'stuff' that get dropped off.

Lloyd mentioned a customer who dropped off a box of stuff while clearing out space at home.  In the process of going through it they discovered an unopened complete carburetor assembly still in the original factory packaging from the mid-sixties!  There is a joy in bringing a piece of history like this back to life, and the joy is alive and well at Mostly Ironheads.  If you're in Southern Ontario, it's an easy ride up north of Guelph to the shop.

This is that racing motor - one of the heads is incorrect, but the rest is intact and very rare!

 These are the cam lobes for that racing head compared to a typical one.  Not only is the racing cam lobe lighter with hollowed shaft, but it's also heavier duty in terms of strength.  Here and here are good primers on cam profiles if you're curious.  Whereas the right side regular cam is designed for long term use and efficiency, the more radical racing came on the left is designed to stay open longer, rev high and produce more power, though it wouldn't idle well, get good mileage or run smoothly.  But when you're aiming for all out speed, you'll put up with that just so you can wind it up and go.  You're unlikely to see mechanical history like this anywhere else in Ontario.

In addition to the restoration work going on, you'll also find an eclectic mix of older, finished air cooled Harleys ranging from customized choppers to more standard rides.  If you're into older, air cooled machinery, this will really float your boat.

Lloyd's area of interest extends from post war bikes all the way up to the last of the air cooled, carburettor fed bikes.  If you're into graphic design, you'll see everything from post war art deco to sixties and seventies disco and eighties futurism in the logos and bike designs.

There are some core elements to Harleys (like v-twin engines), that evolve slowly, but design wise they're much more in tune with their times than you might have assumed.