Topic: Highest mileage on a SOHC?

[madmtnmotors]

Found this thread in a response to a newer thread of the same topic so I'll cover them both.

My 78' K-model currently has about 54,000. Had to replace the valve seals a few months after posing for the attached photo in the burnout pit at the Iron Horse in Ormond last year. Motor started smoking profusely on startup when cold, man them 30 year old valve seals were baked! The old seals actually shattered as I removed them. I had considered going further while I had it out, but she ran fine so I simply replaced the valve seals and the coin sized head stud pocket seals under the cam towers. Put it back together so I could keep on riding, and no more smoke from the tailpipe.

[starkmojo]

My 74 CB750 has 31,200 Miles on it this morning

[ofreen]

The 750 rolled over 125,000 miles yesterday.  No mechanical issues in the last 5000 miles.  If anything, the bike runs smoother than ever.  Gas mileage remains in the low 40's.  Oil consumption is still low.  There has been no need to top off between 3000 mile changes.  I am back to using Spectro.

The only thing that happened was the push throttle cable broke at the throttle tube end at just over 124,000 miles.  I found the pull cable had a broken strand, so replaced that one at the same time.  They both were the original cables.  I called the Honda dealer and found they wanted $96 for the pair.  I was able to get Motion Pro cables for under $35 for the pair.  The Motion Pro cables fit perfectly and have a nice silky feel.

Tappet clearances were checked at 121,000 and 124,000 with no adjustment needed.  I mentioned at 120,000 that a fork seal was weeping, so was going to replace it.  Soon after that, it quit leaking, so I left it alone.  Last week it started weeping again, so will fix it this time.  Also at 120,000, the rear master cylinder was leaking a little.  That quit leaking, too, so left it alone.  Sometimes procrastination works out.

[andy750]

Well done Greg on getting to 125,000!!! And a very good write up that should be the benchmark for future high mileage bikes. I can only hope to get to that figure myself!

cheers
Andy

[Brown Bomber]

19,228mi., 3,000 of which I put on since I bought it last year. It's likely there are more actual miles on the bike. The PO said "The speedometer didn't work for a while." meaning the cable was off. The speedo works fine, and had not been opened until I replaced the gauge faces. I don't expect the miles to climb too rapidly with me, since I have two other bikes I ride often.
Regardless of the miles, the power, throttle response, and smoothness of that old air cooled 750 surprise me every time I ride it. 

[ofreen]

Well done Greg on getting to 125,000!!! And a very good write up that should be the benchmark for future high mileage bikes. I can only hope to get to that figure myself!

cheers
Andy

Thanks, Andy.  I don't doubt you will get there. 

[crazypj]

Just realised, I'm in the 4.7% club 

[Oddjob]

Got a 1972 CB500-4 with 263,000ish on it now, not had a great deal done to it and it still has the original clutch.
Also got a 1973 CB500-4 with 147,000 on it, that ones been fully restored but funnily enough the clutch on that is still original, weird never thought of that before.
Got 2 CB550s, one an F2 with 73,000 and one a K3 which I scrapped but even that had 53,000 on it or there about.

I must add a LOT of the mileages on these bikes were done when I was much younger, putting 40-55k on a bike in a year wasn't unheard of for me in those days, I rode everyday regardless of weather and my family said I lived on a bike.

[brooze72]

Well I think we've got a winner in Oddjob, guys. Even if I lived on my bike every minute for the rest of my life I wouln't come near those numbers, wow.

I rebuilt the top end of mine around 25k but only because it had been sitting for 20+ years. 

[SteveD CB500F]

If you ride or commute every day, it's not impossible to rack up huge mileages.

I remember when my first 500/4 hit 50k miles - I was dead chuffed.

I commuted 50 miles each way for a year (on my Triumph Sprint) - that's 50k miles per year!
The cost of fuel, tyres and oil changes is astonishing!

Steve

[Oddjob]

I've forgotten how many chain and sprockets sets I've fitted to the bikes, quite a few I'd say. I used to use that chain lube where you put the chain in a grease bath and then on the stove, wait for it to get hot and the hang the chain up until the grease reset. Always remember taking one off the stove on day and it was so hot I dropped it, all over my mums kitchen floor  I managed to get it all up with Gunk before she came home but she complained about the smell for days afterwards. I said I'd been washing a part in the sink and it must be in the plug hole 
As I was a Honda mechanic I got all my parts at trade or even free, regularly did up to 1000 miles a week at one point , in fact one day I remember doing over 500 miles on one trip. Thinking back I must have been mad but I didn't seem to be bothered by rain or cold, oh how I wish that were the case now.

[ofreen]

The 750 roiled over 130,000 miles yesterday.  Not much change to report from 125K.  I did a few things in preparation for the Nevada-Utah leg of the relay.  New Metzeler ME88 rear and Lazertec front tires went on.  The right fork seal had been weeping intermittently for the last couple of years, so replaced both, though neither was leaking at the moment.  The last time I replaced them was at 73,000 miles, so they gave good service.  A fair amount of wear was visible in the fork sliders near the top.  That wear was visible the last time I looked back at 73K, and seemed no worse this time.  Fork action is still OK (for what they are).  Like always, the fork oil was replaced with more PJ1 71/2 wgt.

I took the opportunity to clean, grease and adjust the tapered steering head bearings.  Those have been in there since 34,000 miles.  The top set has just the tiniest bit of notchiness evident when pressed hard and rotated against each other dry.  But after being greased and reassembled, they feel fine and no weave is apparent from the bike, so all is good.

Oil consumption was less than a cup over the last 3,000 miles, which included extended 70-75 mph runs during the relay.  Still using Spectro 20-50 conventional oil.  Tappet clearance inspection at 127K showed #2 and #4 intakes about half a thou tight.  I made the adjustments, the first time I've had to change anything there for awhile.  I'll do the 3000 mile service later this week and see if there is any change this time.

The 10 year old Westco AGM battery was cranking the engine a little slowly a few days before leaving for the relay.  Forecast low temps in the teens in Nevada made me decide to replace it before leaving.  A new Westco is in there now. 

The engine is running strong.  Fuel mileage is typically in the low 40's, though it went down to 37-38 on some legs during the relay.  Had to deal with some wind at times.  There has been intermittent oil weeping on the left side of the cylinder block for the last couple of years.  Nothing bad, but it seems to be becoming less intermittent.  Not to start an oil war, but the weeping definitely began a couple of years ago when I got some Mobil 1 motorcycle oil cheap and put that in there, the only time I've ever used synthetic in the bike.  Within a 1000 miles, the weeping began.  I went back to Spectro the next change, and the weeping lessened, then stopped.  But it began again during the relay.  Probably just a coincidence.  ha ha

[HondaMan]

The 750 roiled over 130,000 miles yesterday.  Not much change to report from 125K.  I did a few things in preparation for the Nevada-Utah leg of the relay.  New Metzeler ME88 rear and Lazertec front tires went on.  The right fork seal had been weeping intermittently for the last couple of years, so replaced both, though neither was leaking at the moment.  The last time I replaced them was at 73,000 miles, so they gave good service.  A fair amount of wear was visible in the fork sliders near the top.  That wear was visible the last time I looked back at 73K, and seemed no worse this time.  Fork action is still OK (for what they are).  Like always, the fork oil was replaced with more PJ1 71/2 wgt.

I took the opportunity to clean, grease and adjust the tapered steering head bearings.  Those have been in there since 34,000 miles.  The top set has just the tiniest bit of notchiness evident when pressed hard and rotated against each other dry.  But after being greased and reassembled, they feel fine and no weave is apparent from the bike, so all is good.

Oil consumption was less than a cup over the last 3,000 miles, which included extended 70-75 mph runs during the relay.  Still using Spectro 20-50 conventional oil.  Tappet clearance inspection at 127K showed #2 and #4 intakes about half a thou tight.  I made the adjustments, the first time I've had to change anything there for awhile.  I'll do the 3000 mile service later this week and see if there is any change this time.

The 10 year old Westco AGM battery was cranking the engine a little slowly a few days before leaving for the relay.  Forecast low temps in the teens in Nevada made me decide to replace it before leaving.  A new Westco is in there now. 

The engine is running strong.  Fuel mileage is typically in the low 40's, though it went down to 37-38 on some legs during the relay.  Had to deal with some wind at times.  There has been intermittent oil weeping on the left side of the cylinder block for the last couple of years.  Nothing bad, but it seems to be becoming less intermittent.  Not to start an oil war, but the weeping definitely began a couple of years ago when I got some Mobil 1 motorcycle oil cheap and put that in there, the only time I've ever used synthetic in the bike.  Within a 1000 miles, the weeping began.  I went back to Spectro the next change, and the weeping lessened, then stopped.  But it began again during the relay.  Probably just a coincidence.  ha ha

Excellent, Ofreen! Especially on the "F". Mine is a K2.
I have now experienced the same situation with the Mobil 1: silky shifting and running with increased smoothness and power, but leaks here and there. It has washed the paraffin out of the gaskets, so it will leak until new ones get installed (this summer). I'm going to finally rebuild my engine at the almost 140k mark (139,400+), this year: it runs perfectly, but I can't abide the oil leaks (my OCD, I suppose), so I'm 'going in'. As long as I am there, I'll bore it to 0.5mm oversize, maybe new valve faces or cut new seats. Bought the next-oversize rod/crank bearings, too. Bought new primary chains, as they are reaching near the wear limit, and a new shifter drum to reduce the (reliably selectable) neutrals between 2-3 and 3-4. The compression is still good at 110 (at 6000 feet), could be 120 with tighter valve sealing. Gonna try to find that Spectro you are using, give it a whirl next. Looking forward to that 'new engine feel' this year.

[ofreen]

it runs perfectly, but I can't abide the oil leaks (my OCD, I suppose), so I'm 'going in'.

I'm with you on that.  I knew of a couple 750s years ago that went 150K still running strong, but got to be leaking so badly they were torn down.  The weeping on mine is no big deal yet, it is just that it has spoiled me all these years.  It still weeps less oil than my airhead BMW that has a little over half the miles the 750 has (and is 18 years newer).

[ofreen]

The good ol' 750 passed 135,000 miles today on the way home from work.  Not much to talk about over the last 5000 miles.  A good chunk of those miles was during the second leg of the SOHC4 relay I did and the bike was perfect.  Oil useage is still around a cup in 3,000 miles.  A check of tappet clearances at 130,000 and 133,000 showed no change.  The oil weepage discussed in previous posts has subsided to about nil again.  It is OK with me if it wants to heal itself.

[HondaMan]

I've still been collecting parts (and not enough time!) to install my new pistons and gaskets. I also bought new primary chains and a younger driven primary sprocket, as mine is developing noises now in the needle bearings when it is cold (they go away after warmup). The Neutral light finally stopped working, probably needs a new O-ring to space it properly. That's all I have new to report at 141k miles, though. The oil leak on the cam cover is temporarily plugged with JB Weld (did you know it's exactly the same color as the head aluminum? Can't even see it). 

[Old Scrambler]

My Avitar K3 is just short of 75,000............I put one-over pistons in and ground the valve seats at 68,000 due to one bad seat and rust on the ends of the piston pins.  I had parked the bike for about 8-years and blame the valve on a sketchy mechanic I relied upon to get the bike going  ........Lazy me and did not trust that I was able to do it myself. The original cam chain was still in spec (still in motor) and had less side-play than a DID replacement unit.

I blow a little oil when exceeding 5k rpm............from breather tube and cam-tower pucks (replaced) but otherwise fine.  This bike came new with 105 mains.........now run 120s with stock exhaust and K&N filter in the almost stock box.

This bike has not been my main ride since the first 3-years when new..........about 52,000 then and most of it with a full load and 2-up. It gets thrashed and has been in the redline a lot.............especially when I was using a 4-1 exhaust.  Since the top-end rebuild I have a ticking sound in the head.............after warmup............I've adjusted the tappets twice and its slightly quieter............Its louder under power and quiet when I back-off.   

[70CB750]

Spectro oil? I am still shopping around - Valvoline, Castrol now - will buy Spectro for next change.  I would go synthetic, ale it would start leaking likely.

[heffay]

I've officially put 10k miles on my 350f since I bought it back in the early 2000's... 03, 04?  Something, like that.

I haven't been putting many miles on it because I had a bigger bike for most of that time.  Now that I've sold the big bike, the baby is seeing more miles.  I don't think she minds.   

[Greggo]

I'd like to hear about some mega mileage 500/4's if they're out there..

[TwoBigCats]

my k6 is coming up on 6,000 miles.

[HondaMan]

my k6 is coming up on 6,000 miles.

In another 4000, it will start running good! Man, that's a brand-new bike.

[LesterPiglet]

My 550 only has around 18k. I think the reason being the PO running in to so many non moving objects.

[spot45]

my CB500K has 44,000.  The previous owner put 32,000 on it before I got it.  Other then needing to have the swingarm bushing replaced it still runs strong.

[HondaMan]

I'd like to hear about some mega mileage 500/4's if they're out there..

Mine went 35k+. My brother's went almost 80k, without even one engine disassembly!