1973 Tiger 750 Rear End

[ManInTheJar]

I have been checking and tweaking my recently acquired 1973 Tiger 750 and have a couple of questions re some potential issues on the rear end.

1) The swingarm is powder coated and generally in great condition except for one rusty area near the pivot where I think the fender has been rubbing. I plan to clean off the rust and touch up the bare metal using SmoothRite, or similar, once I am convinced the rubbing has been resolved. The rust is fairly old with no fresh marks (see photo) so I am not sure if a previous owner modified the fender to resolve the issue. There is some clearance between the fender and swingarm, my question is, how much clearance is required and would anyone be able to supply a photo showing this area on their T140 or TR7?
2) The chain guard is very close to the Koni shock but not touching it (see photo) should I modify it to increase the clearance?
3) The brake rod is also very close to the Koni shock (see photo) but not touching it when on the stand, is this normal?. I would be comfortable with a bit more clearance, I cold put a bend in the rod which is currently perfectly straight but that seems a bit of a bodge and wondered if there were other ways of increasing the clearance without fouling the foot peg?

 

[ManInTheJar]

I have done a bit more digging on the brake rod location and ,according to the attached image from the CBS site, I have the correct post 71 arrangement although my pillion pegs look to be mounted much higher as shown on the blown up image of my bike.

 

[Rudie]

2) The chain guard is very close to the Koni shock but not touching it
3) The brake rod is also very close to the Koni shock
but not touching it

Well known saying:-

"If It Ain't Broke, Don't Fix It"​

Koni were never standard shock absorbers on Triumphs.

brake rod
cold put a bend in the rod

... which will straighten when pressure is applied to the brake ...

 

[Rudie]

pillion pegs look to be mounted much higher

The silencer and pillion footrest mounting is not standard:-

. If you do not have one already, 1973 Triumph 750 twin parts catalogue free to read online.

. If you look up the part number of the silencer and pillion footrest mounting brackets then enter it with "triumph" into the internet search engine you use, that will return images of the part. Your bike certainly has additional parts mounting silencer and pillion footrest; also the silencer mounting bracket might not be original/correct for your bike?

. If you enter "1973 triumph 750" into the internet search engine, it will return images of similar bikes. Afaict, silencers mounted in the standard position were beside the ends of the rear axle, whereas your bike's silencers appear to below the axle. Perhaps the bike's previous owner intended this with the additional/different(?) silencer and pillion footrest mounting parts?

 

[grandpaul]

Koni were never standard shock absorbers on Triumphs.

Only three examples of the TSS AV in police and civilian specification were ever made[20](and one bare frame) including one for the late Chris Buckle, proprietor of former Triumph dealers, Roebucks Motorcycles. Not quite to the envisaged 1984 specification, this was made on 27 June 1983 and is, according to the factory production records held by the Vintage Motor Cycle Club, the last complete Meriden Triumph.[21] This is the pictured burgundy-coloured example now on display at the National Motorcycle Museum in Solihull, West Midlands close to the former factory site. It was factory -fitted with Koni rear suspension units and omitted the 'ducktail' in favour of the conventional rear mudguard arrangement.[21]

 

[Rudie]

Koni were never standard shock absorbers on Triumphs.

It was factory -fitted with Koni rear suspension units

You are confusing "standard" with "factory -fitted". I knew Chris Buckle for many years, Roebucks was my local Triumph dealer. Chris's bike was basically to "Executive" specification but with several extras (not just Koni rear shock absorbers) all "factory fitted" but you will never find in any Triumph parts book. Meriden built the bike to Chris's specification because he put up cash money and otherwise the workers involved would have been at home vegetating in front of the TV.

The thread title says "1973 Tiger 750"; perhaps you would like to help the OP by posting how many 73 Triumphs had Koni rear shock absorbers fitted by the factory?

 

[ManInTheJar]

A closer examination of the rear brake mechanism reveals what appears to be a non-standard (stainless steel) brake arm with an extended pivot pin (presumably to move the rod clear of the shock) - see photo. The pivot pin was a tight'ish fit in the brake arm but apart from an old oil seal as a spacer it had nothing to prevent it moving horizontally. The adjuster also had a spacer with plain ends on the brake rod and the rod (stainless?) had signs of being shortened.

For just now I have added a spacer, made by boring out a stainless M12 nut, to restrict horizontal movent of the pin (see photo) and the rod now comfortably clears the shock. I have also shaped the ends of the spacer on the brake rod to match the pivot pin and adjuster, restoring the ability of the adjuster to click positively in place.

Further investigation is required to check if the brake arm differs in length and offset from standard.

The rear footrests are mounted on triangular plates welded between the top of the footrest/exhaust loops and the main frame - not sure why. I plan to move them to their original location but the threads have been shortened so I will need to source replacements with the correct thread length.

 

[grandpaul]

You are confusing "standard" with "factory -fitted". I knew Chris Buckle for many years, Roebucks was my local Triumph dealer. Chris's bike was basically to "Executive" specification but with several extras (not just Koni rear shock absorbers) all "factory fitted" but you will never find in any Triumph parts book. Meriden built the bike to Chris's specification because he put up cash money and otherwise the workers involved would have been at home vegetating in front of the TV.

The thread title says "1973 Tiger 750"; perhaps you would like to help the OP by posting how many 73 Triumphs had Koni rear shock absorbers fitted by the factory?

Hey, I was just parsing out the original reply. I recalled reading about Konis on a factory-built Triumph, and couldn't recall the details. They were 'standard' on THAT bike!\

hee hee

Nice that you keep me honest (or, at least, corrected; because i wasn't being dishonest, just confused with details)