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The Bonnie Maintenance Log

5 Oct 2018

79,xxx miles

Removed leaking float chamber bowel on TS carb - reassembled using Hylomar on gasket and it seems to have stemmed the flow.

14 Sept 2018

79,292 miles

Winter Tear-Down 2012

January 9, 2012

Slacked off valve adjustments and loosened all head bolts to hand-tight.

Found bolt missing from forward head-steadies. That's the bolt I found at Crooks carwash just before the end of the season!

Also found rocker box and head bolts not very tight - perhaps 2 were not much more than hand tight.

  • Change chain
  • Check primary chain tension
  • Done: Replace seals for pushrod tubes
  • Fixed (new o ring) Loose rocker spindles - ?
  • Done Replace headlight lens
  • Tighten forward oil line connections (leaking)
  • Grease swing arm (5k are up)
  • Change handlebars?

January 8, 2012

Removed gas tank, carbs, head steadies.

End of Season 2011

47,550 miles end of season.

September 28, 2011

47,550 miles

Oil change: crankcase and primary chain case.

Replaced cracked headlight lense with new Lucas ($55).

August 27, 2011

46,700 miles

Oil change: crankcase and primary chain case.

August 18, 2011

Been hearing a noise over the past week - kind of a rattle, or sound of a wind-up clock's spring suddenly releasing. Hearing this mostly at a stop at idle as rev's decrease.

This morning I tore down the transmission completely, removing the engine and clutch sprockets. Found nothing loose except for the primary chain being quite slack.

Those econo chains from BSC really stretch a lot!!

Put everything back together (3 1/2 hours to tear down tranny and re-assemble) and put more tension on the clutch springs.

Went out for a two-hour road test - the noise seems to be gone and the clutch no longer is slipping - what a difference in acceleration!

I did notice that the left-hand ends of the rocker spindle's are moving around a bit. Checked the dome nuts at the other end and they seem quite tight. Maybe this is normal, I'm not sure. Or maybe I have too little clearance for the valves? Doesn't seem so though.

August 10, 2011

46,200 miles

New spark plugs - Autolite N3 equivelent (but copper)

Checked points - left them alone

Re-set timing (right cylinder was out a little)

Valve adjustment using this method:

  • Slack off adjusters
  • Insert feeler gauge
  • Tighten adjusters until feeler gauge entrained
  • Loosen adjustors slightly to release feeler gauge
  • Remove feeler gauge, check slack by moving rockers up and down with fingers
  • Back adjustors off slightly and tighen fixing nut
  • Check slack with fingers for same as two steps back

July 26, 2011

Oil change: 45,315 miles

  • Crankcase and filter
  • Primary chain case

July 5, 2011

Oil change: 45,075 miles

  • Crankcase and filter
  • Primary chain case
  • Gearbox (5,000 miles exactly since previous)

June 22, 2011

Installed new rear tire: 44,730 miles

June 8, 2011

44,250 miles

Changed crankcase/primary oil/filter

Clutch slipping less since I changed oil and used 30W non-D and less (~300 ml)

June 5, 2011

Installed replacement oil filter head - no leak!

May 26, 2011

Beginning of season issues:

  • New oil filter head leaking
  • Clutch is slipping

Ordered new front and rear tires today.

Start of Season 2011

April 2011

Start of season odometer reading: 43,3841 miles

Winter Tear-Down 2011

Installed Norton oil filter head


  • Drive chain
  • Primary chain
  • Gaitors

End of Season 2010

September 25, 2010

42,530 miles odometer reading.

Installed new clutch friction plates. No more slipping clutch.

Also, checked cylinder compression:
Cylinder Opposite plug in Opposite plug out
Left 145 psi 150
Right 120 psi 150

September 21, 2010

42,497 miles

Changed crankcase/primary oil (485 mile interval)

September 1, 2010

42,015 miles

Changed crankcase/primary oil (1,236 mile interval)

July 23, 2010

40,779 miles

Went through a period of backfiring and missing after initially running quite well. Eventually, after fretting over valves, timing, and carb, I put the battery back in after having replaced it with a capacitor. Bike instantly begain running normally again with the battery in the circuit.

Bike definitely has more power than before the rebuild.

Had used a bit of oil - about a quart in 500 miles. And the clutch has been slipping occaisionally on two of my last three outings.

Beginning of Season 2010

July 4, 2010

Bonnie back on the road

40,397 miles

Winter Tear-Down 2010

June 9, 2010

Retrieved motor from Costa Zarifi.

CZ changed (40,397 miles)

  • crankshaft bearings
  • high gear bearing
  • mainshaft bearing
  • layshaft bearing, inner
  • layshaft bearing, inner cover of gearbox cover
  • pistons
  • rods polished

Season 2009 Cancelled

Winter Tear-Down 2008

January 6, 2008


  • Rear brake not concentric
  • Rear sprocket broken bolt

Valve job by Frank Holmes

  • valves
  • valve guides
  • valve springs

End of Season 2007

Mileage, 2007
Event Speedo Reading
Beginning of 2006 season (original speedo) 28675
Original speedo out of service 31493
2006 Subtotal (old speedo) 2818
End 2006 season (new speedo) 2550.1
2006 Subtotal (new speedo) 2550.1
2006 Grand Total 5368.1

November 14, 2007

Installed new speedo cable but the speedo still doesn't work. Speedo works with electric drill, cable has no "flitches" in it, but output from cable from gearbox is pulsating. Guess I need a new gearbox.

October 5, 2007

Oil change (crankcase, chaincase), new rear tire, new chain (Reynolds), and new sprocket.

Occaision for another new chain being that I cut the first one a link too short.

July 30, 2007

37,079 miles

Changed crankcase/primary oil (cleaned sump filter only)

Checked points - gaps and timing are right on.

Adjusted idle screws on carbs.

New chain (Reynolds) put into service. Aligned rear tire (twice with new chain, once with old).

Melted down ground leads by shorting out battery (-) with oil dipstick. I should turn battery around so terminals are further away. Put insulated booties on?

Removed front brake lever assembly (from Waldridge I'm pretty sure) due to cracked and broken screw mounting. Replaced with - original? Replacement is upside down (cable inserts into lever from bottom and not top).

July 15, 2007

36,630 miles

Replaced front wheel bearings.

June 23, 2007

Changed crankcase/primary oil (no filters cleaned)

Lubed points fluffs and cables.

May 28, 2007

34,979.2 miles

Changed crankcase/primary oil (cleaned sump filter)

May 25, 2007

Lost left muffler returning from East Hereford.

May 10, 2007

Lower mounting bracket on chain guard broke weld to chain guard. Brazed by welder in Magog.

May 03, 2007

Left front mounting stud on gas tank broke off. Repaired by Atelier des Profs with their brand of liquid steel.

Beginning of Season 2007

March 22, 2007

33,750 new miles (18,000 miles total).

Maiden voyage to Ayer's Cliff and then around lake Memphremagog. Sixty-eight miles in all. Issues:

  • Vibrations
  • DS gas tank mounting stud loose

Winter Tear-Down 2007

March 20, 2007

Front forks

Forks got new seals, o-rings, and bearings. They also got a used DS lower fork leg due to stripped threads on original unit. Replacement obtained from Don Hutchinson had a different type of drain plug (elongated tip - for sediment?) and also had threads in the mounting lug for the rear front fender stay. I also ordered a new dust cover but it was not a good match with the other original so I put back the original one. I did note that the new dust cover threaded on quite snugly while the old one threaded on fairly loosely until the last little bit.

When I took apart the forks I found that the circlip had come off of the shuttle valve on both sides. One of the check valves is a bit beat up but I put it back in because replacement was not immediately available.


  • Seat
  • Handlebars (low profile "W")
  • Exhaust pipes
  • Mufflers
  • Brake switch nuts/bolts


  • New (short) throttle cables
  • New front brake cable

Things done/not done

  • Oil pressure blank Blanking plug (Waldridge) installed
  • Repair taillight connection New bullet crimped to lead
  • Get a new fuse lead Reused part of old fuse holder
  • Have new rear tire installed New tire installed
  • Move ground lead from instrument deck Grounded beneath deck with short fine-thread bolt
  • Restrain harness inside headlamp shell Not done
  • Replace corroded spark plug leads Replaced
  • Check out primary chain case oil level plug Is something stripped? Not sure.
  • Replace points Replaced DS cylinder points (forward set) but not TS
  • Adjust points and timing
  • Valve clearance Adjusted
  • Tops for carbs with no choke holes Not yet, still epoxy
  • Reassemble carbs without spacers for cables Done, no spacers.

January 28, 2007

Have stripped Bonnie down to engine in frame, fenders, front end, front tire, oil bottle.

Issues/things to do:

  • Oil pressure blank?
  • Repair taillight connection
  • Get a new fuse lead
  • Have new rear tire installed
  • Move ground lead from instrument deck to headlight shell bolt?
  • Restrain harness inside headlamp shell
  • Replace spark plug leads (left-hand one is completely corroded)
  • Check out primary chain case oil drain
  • Replace points
  • Adjust points and timing and valve clearance
  • Tops for carbs with no choke holes
  • Reassemble carbs without the spacer for the cables

End of Season 2006

December 25, 2006

Event Speedo Reading
Beginning of 2006 season (original speedo) 28675
Original speedo out of service 31493
2006 Subtotal (old speedo) 2818
End 2006 season (new speedo) 2550.1
2006 Subtotal (new speedo) 2550.1
2006 Grand Total 5368.1

November 24, 2006

33,629 miles

(interval 929 miles)

Crankcase: Quick Change (filters not removed, sump not drained)

October 14, 2006

32,700 miles

Changed crankcase/primary oil

September 16, 2006

31,884 miles

Rear tire flat.

Installed new K-70 tire and tube (D'eauville)

September 10, 2006

31,700 miles (new speedo)

Changed crankcase/primary oil

Cleaned and lubed chain

Also, installed new cables for carbs and clutch and adjusted timing and idle. Bike is running like new!

September 7, 2006

Replace speedometer with a rebuilt from Frank. Old speedometer stopped at 31, 493 miles (see table above).

September 1, 2006

Bonnie popped out of 4th gear yesterday and left me in neutral with no gear changing action from the foot shift (no clicks, just up and down).

Coasted back to Dave's driveway where foot shift still didn't work, but then it started working about five minutes later. Went on to ride for several hours with no problems.

I was cranking pretty hard going up the hill at 70 when she popped out.

August 25, 2006


Changed crankcase/primary oil

Before leaving on trip down to NH to meet Richard Swartwout

Stopped at Frank Holmes Brit Bike Barn, former home of Bonnie. Frank was effusive in praise of the bike. When he heard about the top end job and subsequent oil burning he ran into the shop and came out with spark plug wrench and compression test in hand.

Both cylinders measured between 165-170 after 5 or 6 kicks.

After the rebuilt they measured around 135, but I didn't hold the throttle wide upen the way Frank said to.

August 12, 2006

After a spate of headlamp bulbs breaking I solved the problem by putting a small dab of grease on both contacts of the last bulb I put in. The contact assembly twists on quite stiffly and evidently without the grease it had been stressing the bulbs base with respect to the glass, resulting in breakage in quick time.

July 30, 2006

Replaced exhaust pipes after striking rock in the wake of a road grader.

I asked for 'skinny' pipes this time instead of the 'fat' pipes I got last time from Don Hutchinson. The first set had a bad bend in the right-hand side pipe and I had to return them for a second pair.

I'm not totally happy with this set either - they go on but I think the angles between the pipes and the jugs are not completely right - I have a hard time sealing the exhaust gasses in at that joint.

Beginning of Season 2006

28,675 miles.

Winter Tear-Down 2006

March 15, 2006

Completing winter 2005/2006 maintenance at 28,675 miles

Compression after rebuild: 135/135.

Top end rebuild, including:

  • Valves (Black Diamond)
  • Springs
  • Rings
  • 1 valve guide
  • 1 cam follower tappet


  • Front wheel bearings removed, cleaned, repacked and reinstalled
  • Rear wheel bearings replaced.

Gas tank

  • Repaired
  • Painted

Oil tank

  • Repaired
  • Painted

Frame and most brackets and tin

  • Powdercoated


  • Updated


  • New wiring harness (See wiring notes)



  • Swing arm
  • Front and rear wheel bearings
  • Steering head bearings
  • Brake pedal
  • Brake cam bolts

Pre-rebuild top-end spec's (Patrick Degens') at 28,675 miles:



Measured Specs Action taken
Valve stems inlet .3082 & .3082 .3095-.3100" Changed
Valve stems exh .3075 & .3097 .3090-.3095" Changed
Valve guides inlet .3129 &.3132 .3127-.3137 Kept
Valve guides exh .3129 & .3128 .3127-.3137 Kept
Tappets inlet .3100 & .3110 .3110-.3115 Changed 1
Tappets exh .3110 & .3115 .3110-.3115 Kept
Piston clearance .0062 & .0062 .0046-.0061 Kept
Rings (all ) .018 to .025" .010-.014" Gap Changed
Cylinder bore (+.020) 2.8152 & 2.8151" 2.8148-2.8153 No rebore

Note: the following part numbers reflect the sealing condition found from '70 until '73, to which Bonnie was evidently upgraded previously.
Part Number Part Description
E-7310 bottom pushrod tower sealing o'ring
E1-1283 top pushrod tower sealing o'ring
E-4752 sealing ring (white, square-edged ring)
E1-1707 sleeve (aka wedding band!)
E1-2575 correct push rod tower number

January 14, 2006

Picked up powder coated frame, brackets, and tin.

End of Season 2005

December 8, 2005

28,675 miles

Last ride on 1 December.

Tearing bike down for winter maintenance.

September 23, 2005

Received replacement left-hand carb and it works just fine.

Now that both carbs will tickle, Bonnie starts right up on two cylinders again.

September 8, 2005

Installed new Amal concentrics.

A few issues: 1) left carb won't tickle (just like old right carb) and 2) can't properly thread air cleaner onto the left carb.

Idle screws are right out giving no idle unless throttle is held open at the twist-grip - however, it started on about the third or fourth kick and on a short test run down the hill, and a way past the Stanstead county line it ran very well:

No coughing and missing as before and pinging has subsided greatly (gone except under stress?). The formely jerky low and mid-range (2,000-3200rpm) throttle response is now very smooth. I?ve never been able to come up the hill as slowly and negociate the first corner with no engine ping.

Top end? Had no helmet on and only took her up to just under 70 on the winding turns of gravel road. It did seem to have a bit of a dead spot up there, but hard to tell.


Replaced front stay. New one broke in less than two hundred miles.

May 7, 2005

23,750 miles

  • Lubed chain (700 mile interval)
  • Removed and cleaned left and right carbs.
  • Checked timing with new strobe - bang-on.
  • As per list responses, adjusted idle air screws to eliminate popping on runoff.

Beginning of Season 2005

April 14, 2005

23,045 miles

Winter Tear-Down 2005

Began readying Bonnie just about a week ago. Had a new rear tire mounted and replaced the wheel with lubed chain.

Then I checked the valves - exhaust seemed ok, but the inlet valves seemed to have no clearance at all so I readjusted them.

Reassembled everything and gave her a kick outside - started right up on the first kick, but only on the left-hand cylinder.

Spent four days working on the electrics because the right- hand cylinder's spark looked weak to me - ordered new coils from Moto Montreal and they arrived next day by express mail but they were the wrong ones so I drove to Montreal and exchanged them.

After reassembling with new coils she was still hitting on only one cylinder so I pinged the BritIron mailing list. Pete Chartrand was first to respond and he was right on when he said to check the two small holes in the needle jet. Passed a slender wire through them, reassembled once again and Bonnie roared to life on both cylinders on the first kick.

Took a short spin down to AC and back and then took a ride to Magog today after first going to Crook's car wash in the village. It was about 5 degrees C but I had on two pairs of pants and my riding jacket with winter liner so I was very comfy.

End of Season 2004

October 29, 2004

23,045 miles

Changed crankcase/primary oil (1,200 mile interval)

Cleaned and lubed drive chain(530 mile interval).

October 26, 2004

22,980 miles

Dip switch died this week - shorts out battery and blows fuse on high beam.

October 10, 2004

22,516 miles

Chain cleaned and lubed

New chain's master link came off very easily using a small drift to punch the connecting link out of the cover piece. Used the needlenose vicegrips to put the cover piece back on far enough when replacing and I think it went a bit easer than the first time, but still very tiight.

While checking tire alignment after replacing chain I noticed that the rear tire is practically finished - just a tad better than when I replaced it on July 23 at 21,100. That gives me 1,400 miles on the tire - can the gravel be that hard on tires? I think something?s wrong here. I?m estimating that the last tire (put on by Frank) lasted in the vicintiy of 7,000 miles.

Also noticed yesterday that all Bonnie?s lighting was out. Thought it?d be a connection on the lighting switch but instead it was the feed to the lighting switch from the ignition (brown/white wire on ingition switch connection the farthest forward).

September 25, 2004

21,845 miles

Changed crankcase/primary oil (1,259 mile interval - oil was quite dirty)

  • Cleaned and lubed drive chain.
  • Cleaned air filters in kero and blew them out.
  • Replaced oil line clamp on oil bottle connection with the filter - old one stripped out when I replaced it - I have to learn not to over-tighten these.
  • Installed the new (Tsubaki) chain with a new masterlink - very tight master link cover plate - as Chris at Moto Montreal showed me I used vice grips and an old link cover plate to squeeze the new one together far enough to get the clip on - and it was quite a job at that. Will have use a drift to get the master link off the next time I maintain the chain.
  • Replaced lighting switch in headlight because the old one was getting very tempramental about making contacts.
  • Replaced headlight lamp due to burned out low-beam filament.
  • Ready for Fall riding!!

September 4, 2004

21,108 miles: chain cleaning and lube.

September 2, 2004

Replaced metal cover on drive side which I lost several days earlier on a ride around the west side of Lake Memphremagog in Vermont.

August 13, 2004

20,568 miles

Changed crankcase/primary oil (833 mile interval)

Cleaned and lubed drive chain.

August 10, 2004

Adjusted the ignition timing using a stroboscope. Hard to see but then I marked it with black magic marker and waited until dark (bike was outside).

Also managed to turn both headers yellow (even some purple on the drive side) - 2,000 rpm while stationary is enough to overheat the bike.

Once I could see the timing mark under the strobe it only took four or five seconds to check a setting. I think trial and error is best because my arms aren't eight feet long. It would be good to note adjustments in terms of advance and retard for future reference.

July 23, 2004

20,100 miles

New rear tire and tube.

July 14, 2004

19,911 miles.

Cleaned and lubed chain

July 12, 2004

19,825 miles

Changed crankcase/primary oil (1,060 miles interval).

Also installed new oil hoses between oil tank and oil pump junction block. New hose is softer, more pliable than the old. New clamps seem to tighten it right down and there is no longer any leakage from the oil pump side connections where there definitely was before. There still, however, seems to be some oil leaking from somewhere.

July 6, 2004

Since 'completing' restoration reassembly I have lost, or nearly lost:

  • Front fork cap bolts (had to come home hand-tightening the remaining one)
  • Rear axel nuts
  • GearshiftK
  • Kickstarter
  • Rear shocks (tops and bottoms both sides nuts nearly off the bolts)
  • Engine mounts
  • Front fork pinch bolts
  • Yoke pinch bolt

June 14, 2004

Lost a chain in Rock Island. Evidently I didn't snap on the master link clip after replacing fresh chain. Had none to fit at home, got towed home by Dodge dealer. Picked up new link next day at Moto Montreal.

June 11, 2004

19,400 miles

lubed chain (medium chain bar oil overnight and drain).

Beginning of Season 2004

May 26, 2004

18,765 miles

First ride of the season.

Winter Tear-Down 2004

Restoration reassembly completed (see separate document).

Changed crankcase/primary oil

Changed gearbox oil

End of Season 2003

November 25, 2003

Mileage: 18,764.

Last ride of the season.

October 12, 2003

18, 200 miles.

Changed crankcase/primary oil (inc. filters)

Failed to tighten primary oil level screw, evidently, and lost it on first 30-mile ride. Doesn't seem to be any damage to chains or clutch, though. Found a screw with thread close enough (might be a tad loose in the thread) for a temporary replacement.

Aligned rear wheel using a straight-edge (1 x 4 pine) but was way off. As soon as I rode (same ride as above), I could feel the bike tracking to the left and acting weird. Re-aligned using instead a piece of mason line - much better!

September 26, 2003

Went to Moto Montreal. Talked with Chris. New concentric carbs are $200 apiece. A damper would run about $60 in parts.

Picked up headlight and speedo bulbs (bayonets) as well as a set of new footpeg rubbers.

August 30 , 2003

Oil change 17,150 miles. Includes primary chain case and crankase. Washed all filters in kerosene.

Adjusted clutch - just right now at a little under a half turn out from plate lift. Doesn't seem to be slipping now, but gear changing is smoother. Noticed today that going very slow and easy from neutral to first at a standstill seems to go quite easily.

August 29, 2003

Thought I had tracked down the dead RH cylinder problem to a bad condenser (points for RH side seemed to be arching - a faulty condenser according to Haynes), but after replacing both condensers ($36 plus tax from Moto Montreal) the problem persisted.

I went over everything again - hooked up the ignition switch correctly, etc. Finally switched plug wires and watched the problem move from Right to Left cylinder as I turned over the engine with plugs out and grounded, watching for spark.

Got two new wires made up by Magog Auto Elentrics (Sherbrooke street) and Bonnie started right up on two cylinders.

Meanwhile I have removed the ugly bracket that held the horn and the condensers and mounted the condensers directly to the frame there instead of to the bracket. Of course I also removed the horn relay and all the extra baggage wiring.

Starting to look a bit cleaner.

Couldn't go for a ride afterwards due to rain, so I cleaned the air filters instead.

August 27, 2003

Well, I may have fixed the intermittant ignition switch problem, but now the right-hand cylinder is completely missing at low revs. I went out twice since cleaning up the switch corrosion and the problem gradually got worse and worse to the point that the r-hand cylinder hardly fires at all until rpm's are way up and even there it bogs.

Yesterday I could see that the spark on that cylinder is very weak. I cleaned the plugs and points and checked all gaps - .020 plugs, .015 points (they were both very tight, plugs were a nice light chocolate brown).

I also checked the ignition switch - I think it's connected correctly, but I'm not 100 percent sure.

I pulled off the tank again today and looked at all the coil connections that I re-did the other day before discovering the corroded ignition switch. Everything looks ok.

Could be capacitor or coil? Wire? The spark was weak from plug end of plug wire to ground with the bike running (on left- hand cylinder).

Tomorrow I need to check origins of the brown/white and white/brown wires to ignition switch with VOM to see if the ignition switch is truly hooked up properly:

I'd swear that before I played with the ignition switch the first time (below), the lights would not come on until the ignition switch was turned on, whereas now the lights will remain on after the igntion switch is turned off.

August 24, 2003

Bike was stalling two nights ago when LA and I went for a ride to Magog and North Hatly and today it died completely when I got to the bottom of our hill.

I found the problem - bad contacts (corrosion) on the ignition switch. Cleaned them up and its working fine - this should also fix the anomly that I noticed when I drove to Sherbrook the first time this summer- bike stalling when making a left-turn from a light. This was because turning the front wheel to the left moved the big plastic-covered part of the wiring harness that goes up to the headlamp shell and that was what was making the ignition switch contact intermittant.

August 1, 2003

16,500 miles

Changed crankcase/primary oil

Tried adjusting the clutch again - to about 2/3 of a turn, clutch still drags.

21 July, 2003

Clutch was slipping. Manual says to back 1 turn off of where plate lifts, bike was adjusted right to where the plate lifts. I backed it off one turn and the clutch is now dragging a bit too much - gear changes are a bit chattery.

Start my Bonnie log

June 28, 2003

15, 768 miles.

End previous owner log

May 23, 2003

(Last entry by Frank)

New fork seals and gators.

August 12, 2002

Retorqued head, set valves, changed gear oil.

August 10, 2002

190cc 30w oil in front forks.

August 8, 2002

New front tire and new front fork gator.

Deglazed front brake drum.

July 8, 2002

New 20" (or 15 thousandths inche) over pistons and new valve guides.

June 23, 2002

New K70 rear tire.

New rear brake shoes.

New center stand spring.

Adjusted primary chain.

June 22, 2002

(Start for Frank)


Disassemble carbs, replace needle jets, check floats, clean airways.

No sign of oil leakage past guides.

# 3 slides

# 190 mains

Rear speedometer drive: [3 or B]65330/168

Rotor: 15/12 =1.25-1

Beginning of log: T120R Engine & Frame NC00125

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