72 Combat ....2 years of ownership

I've had my 72 Combat for 2 years this month and have done quite a bit on with lots of useful input from this forum.
So far I've:
Stripped and checked the swingarm-it has extra fixings fitted by a PO.
set up the isolastics ( mirrors become clear at 2500/3000 rpm) although grabbing the rear wheel there is movement.
made and fitted a tie end type head steady
rebuilt and fitted a set of Koni shocks.
Recently new rear tyre.
Both tyres are Dunlop TT's ( 30 psi front and rear....too high?)
Upgraded the charging system.
Have nothing to the motor as it runs very well.
Recently did a 1000 kms in one weekend.

The front forks are supposedly fitted with progressive springs ( yuk)
I have a lansdowne kit to fit over the winter
The front brake :roll: is stock.... m/c needs to be reduced.

Its mid summer here and I went for a 300 km ride
I really like riding it, the excellent torque and the sound...and that feeling of riding a bit of history.
However..... I find the handling strange.....the bike seems twitchy and skittish on the road at over 50 mph, it takes me a whole morning to 'get into it" Am I expecting too much from a 1960's design?
I race a R90 BMW and commute on an R65 and both of them seem so much more 'planted" on the road.
I can really throw the R65 into corners on the road....I would not be keen on the Commando.
I'm thinking oversprung?...and maybe I need to get the front end sorted.
Any tips?
Thanks in advance
John

Ah, any happy combat owner. Good for you! Handling department...the Commando should handle considerably better than a boxer twin. There was a pretty good article in issue 301 of the Road Holder magazine, NOC club publication, that talks about getting the engine aligned with the frame by making sure the front and rear ISPs are perpendicular to the frame axis and no binding. The author mentioned once aligned he could ride hands free without the bike drifting to one side which is what most of us experience.

The author mentioned once aligned he could ride hands free without the bike drifting to one side which is what most of us experience.

Click to expand...

you mean take both hands off the bars at say 60mph and the bike will track dead straight while your own weight is absolutely neutral?

I have never experienced that on any Commando I have ridden

the weight of the nearside with drive chain and primary outweighs the right side and I have always had counteract that by moving by body rightward on the seat when I have done the hands off stuff

Combats are the Cream of the Crop and most dangerous Commando made d/t great power to thrust you beyond the un-tamed isolastic tolerance in rebounding HELL!

Your post is more evidence why I am so ho hum BFD on what ever head steady installed, its not where the taming help most needed, which is rear ward of rear isolastic mount. Then front link is next most improving, then don't really need top link but to smooth out the the wind gust jiggles, that no one even notices because they ain't got the rump link right or are too rigid with sway plates non compliance.

Non one has compliant tri-linked Ms Peel deal so limiting my response to ordinary un-tammed Cdo's. I can not ride very hard on my regular Combat w/o out lowering front pressure a bit less than rear or the front traction vector tends to over whelm the rear grip vector and onsets THE Hinge. The faster ya go the more important to rear boss in on leaning control and the less the front tire. If I air tires too high the ride get rougher but most so the bouncing that onsets THE HInge sooner and more harsher. Play with front pressure till noticing the steering gets lighter and more neutral but can still Hinge on ya at a bit higher speeds, so creep up on limits in special places.

Before ya try resleeve m/c, try poking red hot nail poking out the tiny rubber restrictor hole. Its helped me wear out front tire in only two rear tires while prior front lasted 3-4 rear tire use ups. The hole don't change the ratio ease but prior I could squeeze as hard as i could and not hardly slow tire to squeal, after wards could squeal front over high way speeds and had to back off below 50 d/t lock up. Very secure brake control improvement to me, so only traction is limiting factor not brake power.

About any solid mount cycle can way out handle a '70's antique rubber baby buggy, but you don't know what you are missing out on with a tr-linked iso Commando you can't even feel under you d/t the smoothness and harsh G's on very edges in gusty condition on lumpy roads that lift tires of the corner cripples but so so secure on flexy non rebounding Commando power planting.

Rode Trixie ordinary Combat yesterday in 40's F to work at up to 90's on great paved surfaces and nice banked easy sweepers to be pissed off scared how much it was Hinging and me having to knee grip tank and plant butt to stabilize bars and prevent the weave from building up even w/o going any faster. Commandos are very dangerous cycle to play with moderns on so best not. OH sure Combats at WOT can keep up in the opens with most moderns till 120 or so but it will not stay in control like moderns can in much leaning turning as you already know.

"set up the isolastics ( mirrors become clear at 2500/3000 rpm) although grabbing the rear wheel there is movement."

When you say there is movement at the rear wheel, is that movement within the ISOs themselves or is this play in the swing arm? To get the rear wheel to move back/forth with the iso system takes a good bit of force but if you can "wiggle" the wheel/swingarm back and forth, that's a swing arm issue that will easily cause the sort of handling problem you describe. With good isos and proper swing arm mounting/bushings/spindle clamp, you won't be able to move the rear wheel back and forth by just grabbing and pushing/pulling.

The swingarm spindle can develop play within the swingarm tube over time and a pair of swing arm clamps will eliminate that problem. My commando was, at best, a mediocre handler until I installed swing arm clamps after realizing there was play in the system. The difference was pretty dramatic.

Might be some other problem you are having but I'd sure take a close look at the swing arm and consider new bushings and clamps if they are not already there.

Hi Mike 996, I suspected the swingarm and pulled it all down and lubed it, there is no play to speak of, any play would be the iso's.... I did the feelerguage setup at 10 thou from memory...
its got the 'vernier' set up with the round drilled adjuster.
But you can definately see the wheel move when you grab it.
The swingarm also has nuts welded on and bolts lockwired to hold in the pin.
I might look at the adjustment again, the whats the lifespan of isos, I figure this bike was 'restored' in the early 90's.
cheers

Well, I'd say the Iso donuts are definitely suspect at that age. I use .006 iso adjust at the front and rear and, as I said, you can't feel any movement at the rear wheel unless you basically sit on the floor, brace a foot against the frame and pull the wheel. Under that condition the wheel, swing arm, engine - the whole shebang within the ISO envelope - can be moved but it won't move by just grabbing the wheel.

New donuts are much harder to move than old ones which could be torn/crumbled. Also, the iso tube itself could be rusted out as could any/all of the snap rings that keep the donuts in the proper position on the tube.

Pull 'er apart and check 'em out! (but order all new parts first!)

hobot said:

Before ya try resleeve m/c, try poking red hot nail poking out the tiny rubber restrictor hole. Its helped me wear out front tire in only two rear tires while prior front lasted 3-4 rear tire use ups. The hole don't change the ratio ease but prior I could squeeze as hard as i could and not hardly slow tire to squeal, after wards could squeal front over high way speeds and had to back off below 50 d/t lock up. Very secure brake control improvement to me, so only traction is limiting factor not brake power.

Click to expand...

Steve, I've seen you mention this several times in past posts. Not trying to do a thread "hi-jack", but what are the mechanics behind this claim? After reading about all the problems folks have had after professional resleeving, I'm tempted to try your suggestion.

Has anyone on this forum tried this brake "fix"?? I'm really curious if it's "Fact" or an "Urban Ledgend"? ...well in Hobot's case, I guess it would be labeled a "Backwoods Legend"... :lol:

72Combat said:

Hi Mike 996, I suspected the swingarm and pulled it all down and lubed it, there is no play to speak of, any play would be the iso's.... I did the feelerguage setup at 10 thou from memory...
its got the 'vernier' set up with the round drilled adjuster.
But you can definately see the wheel move when you grab it.
The swingarm also has nuts welded on and bolts lockwired to hold in the pin.
I might look at the adjustment again, the whats the lifespan of isos, I figure this bike was 'restored' in the early 90's.
cheers

Click to expand...

Have you checked your wheel bearings for play ?
sam

I'd try better tyres first,if you're still running 19s the avon road riders are all right in the dry, aithough could do with a wider rim , 100/90 front and rear is ok a bit neutral and sometimes felt abit slow to steer, I now prefer a 90/90 on the front and wider rear rim.Don't use the progressive springs with your lansdown damper kit, made mine very harsh, and yes my swing arm, rear wheel flexs but does not have free play

I had practiced for life death awareness to avoid, a total clapped out loose swinging arm, 1/4+" free slide gaps of worn away iso mounts on old tires '71 and it was one of the nicest smoothest surest Cdo's I've tried - it only gave a mild twitch on zig zag tests and initial tips into decent sharp turns, but I sure learned try no held sweeper leans over 75-80 mph as it started The Hinge then. Mainly could feel the old tires doing their thing, so ties remains top of handling features to fix first.

Seems many think my hobby is mis-leading everyone to their horrific deaths - you are all on your own for that just riding cycles.
I've one fella who did the red hot nail poking and complained to me it did not make his Norton brake a two finger lockup, then added prior had to plan way ahead for turns as no matter hard hard squeezed the brake didn't get any more effective, after wards said it stopping like 1/3 faster-shorter and could make tire noise at will, so let that be a warning to you on hobot myth.
There is No Reason for the stupid tiny restriction but maybe to mimic the drum brake effort and fade and No resleeve kit has any restriction at all. I now feel most the improvement of sleeved kits is no restriction rather than better ratio. Try it and see.

I wet down to the garage last night and by grabbing the wheel and frame could see about 3mm gap between the muffler and swingarm.....I'm leaning ( no pun intended) towards the isos being old and tired.
Leads on to the next question are there good and bad isos on the market..... I've already had the clutch cable where the nipple came off after a matter of hours......
Wheel bearings are good.
I recently replaced the rear Dunlop TT with a Dunlop TT mainly to match the front as it was good..... last few rides on the worn but legal rear bike was very twitchy over any imperfection in the road..... new tyre sorted that.
They would not be my first choice of tyre as they look too 'chunky" but the range on 19" available here is limited to ones made of slipothene and $$$$$ Avons......if only Bridgstone made a 19 rear.....I really like BT 45's.
cheers
John

mike996 said:

The swingarm spindle can develop play within the swingarm tube over time and a pair of swing arm clamps will eliminate that problem

Click to expand...

What's a «Swing arm clamp»?

Fritz

bad_friday said:

mike996 said:

The swingarm spindle can develop play within the swingarm tube over time and a pair of swing arm clamps will eliminate that problem

Click to expand...

What's a «Swing arm clamp»?

Fritz

Click to expand...

not-another-spindle-thread-t5978.html

[quote="72Combat"
They would not be my first choice of tyre as they look too 'chunky" but the range on 19" available here is limited to ones made of slipothene and $$$$$ Avons......if only Bridgstone made a 19 rear.....I really like BT 45's.
cheers
John[/quote]

Not sure what they cost down there but here Avons and Bridgestones are very reasonable.

1up3down said:

The author mentioned once aligned he could ride hands free without the bike drifting to one side which is what most of us experience.

Click to expand...

you mean take both hands off the bars at say 60mph and the bike will track dead straight while your own weight is absolutely neutral?

I have never experienced that on any Commando I have ridden

the weight of the nearside with drive chain and primary outweighs the right side and I have always had counteract that by moving by body rightward on the seat when I have done the hands off stuff

Click to expand...

Neither have I, but willing to try what the author wrote just in case

I've seen and rid 3 Cdo's with original cushions in there to find some had softened up while other had hardened up but non of cushions even the squashed down age rotted ones allowed any loose slack of rubber in tube slop. Grab rear wheel about axle center and shove side to side and watch or feel for what the front iso gap is doing. Also grab wheel top and bottom and twist in vertical plane and watch swing arm joints as well as the front iso gap for sense of where most the slop is. I ground off 45' bevels to remove like half the rubber contact rim area and love the sooner isolation onset and no botther to the zig zags and flings i enjoy so much.
It the rubbers allowed the side motion then they should just drop out of finger push out of tubes, but we hardly ever hear of that happening. You can't really tell what the iso's and swing arm or what ever is doing Until Two Good tires mounted at proper inflation and front to rear balanced, or just guessing, even if finding something that seemed the obvious issue other than tires. For a while with new tires my Combat tracts hands off almost down to walking speeds and then pretty much self corrects before flinging me off. After a few 1000 miles much speed up before letting go to fix helmet or jacket with both hands. Crisis of stinging insects to release in time can surprise ya on tire conditions if not already aware.

" However..... I find the handling strange.....the bike seems twitchy and skittish on the road at over 50 mph, it takes me a whole morning to 'get into it" "

youll find it stops it if you go faster , the suspensions to hard for touring . 9/10ths , at the limit , its started to work nicely . :? :cry: Bother .

Iso's set ' Non Binding ' ( they bind at .002 but free off ) Over 4 1/2 Id detect slack , chassis to drivetrain . So runnim at oo25 to 0045 .
Was never entirely convinced the swing arm pin was entirely ' secured ' infallibly or immoveably . One area requireing thoroughness .

TRIANGULATION in plane of support . Easy ways throw on a Norvil type top mount / headsteady .
Im convinced a extra Iso under the trans transfoms ballance .

=========================================================================================================================================
If on chipseal , the things rough .Feels like the bars are shakeing / vibrateing , & you check it out & find its the Road Shock .Or what they called ' stiction ' .
this is when fair ( FEAR ? ) howling in a drift at 5.000 rpms gwts it finely balanced & dragging things . Unscraped footrest rubbers on a triumph were uncool .

However , this is liable to put a hole in the sceneary . Id though 90 knots a good limit on hidious irregular chip seal roads . Anythingelse'd have the STEERING DAMPER wound right up .
another cost cutting proceedure . NO steering Damper . WHAT are things comming to . ( matching the el cheapo whizz bangs on price . ACTUALLY )

Right . Well .
The TT100s were more ' Camber sensitive ' particularly as the front was a KR76 & could follow the contours if you hadnt taken the initiative .
mutter fume.
The Roadrunners 3.60 & 4.10 were a good deal more relaxing to live with.
However a 4.10 front & a 4.25 : 18 rear would give you some rubber .

Matched sizes yore rideing / working , the front . & watching the rear doesnt go awol , rideing gung ho .
say leant over draging , neutral .Both are working as hard . If youre on the limit hower yer gonna get any power down .
other than easeing / milking . A bit more bite on the rear alows a bit more anticipation & balance .

Conventionally you lean & run the bends . It so frigging quick nothingl stay with it . On EXIT ( NOT apex ) the tourque'll slingshot you away .

this is called maintaining corner speed . It ensures that any other road users are obstacles . Ands a fair strain on the nerves .
A bit more rubber aft lets you ride it like a Triumph . & the nder Iso mod . Drift or throttle steer . :lol:

Yea . I recon the frames a bit light & not entirely dimensionally stable motocrossing at the ton . But itd match anything of the era , & had better balance .
Rideing tecnique needs adapting to differant chassis characteristics .

& save up for a steering damper , too . . .

So Matt are you floating on a raft some where in Kweensland? Nice and dry over here in the homeland.....

Down the Big Smoke at the moment . But Blackheath in the Blue Mountains . Highest point in the place .
If it keeps on riseing , we'll be the last ones to go .