Hi from cheshire

[Legin]

Hello,
I have just bought a 750 k1 1971 built late 1970 and red that was imported 3 years ago so Im second owner. I would descibe it as good condition although it has taken me nearly 3 days to get it running half decent. The seller paid the outfit that mot,d it to set it up as he wasnt happy with the running. Well just say the girl on the bacon counter would have done a better job, timing, floats synchro all about as far off as possible it barely ran and now that power is restored the clutch slips.
Anyway despite this I love the bike and will start renovating it, the main areas I find disturbing are front disc performance which surely cant be this dire (best pads anyone) and stability at speed when going over white lines and cats eyes, am I expecting too much or is it tyres and shocks ? Best save the questions I guess.

[K2-K6]

Hello and welcome to the site. Another 750 out and about, that's got to be good.

White lining is normally tyres first, try going over pressure about +6 psi and see if it improves if so then it's the profile worn a bit square, usually on the rear as they generally track quite straight as standard.

Front brake is capable of not bad stopping if working properly ( all pivots and piston free to move correctly) good thread just happening in "350/400 front brake" to give you the lowdown if unfamiliar.

[K2-K6]

Oh forgot about the slipping clutch, used to thrash these a bit in there prime and always used stronger springs to make them bite and not wear themselves out but the usage was quite extreme.

Oil, if anyone has used a friction modifyer in the oil it can do this so if you are unsure what's in it you may be wise to do a change. Always used the original type Castrol GTX in these motors and never had any problems with bearings etc lasting very well.

Make sure that there is a small bit of slack in both the adjust screw/nut and the cable to ovoid them holding the plates slightly open as the clutch is fairly small diameter and can't hold the torque if you impose any partial release on it unintentionally.

[BigAl (Alan)]

Hi and welcome to the site.
Sounds like a bit of TLC for the old girl, had similar problems with my K4, so post those questions and we will try and help.

Alan

[UK Pete]

Hi enjoy the site, i also have a k1 and really enjoy riding it, the front brake on mine is really good for a 1971 single disk, so there is hope for yours, a total strip and rebuild should do the trick, red is a good colour same as mine, what tyres do you have and how old are they?  try and post some pictures for us to see.

pete

[ritchie-k1]

Hi Legin, Sounds like my K6 was after 10 years laid up, no brakes and a slipping clutch. Sorted out a badly worn out clutch with a clutch kit from Dave Silvers, re-placed all of the seals and front pads at the front end but the brake still isn't inspiring despite a good front tyre running the right pressure and dot 4 fluid with goodridge lines. My back brake isn't good either as the drums is out of round and is on my to do list. Enjoy the bike matey.

[K2-K6]

My K6 (not currently in use) also has an out of round rear drum, possibly cracked lining that I'll have to sort out at some point.

I don't feel that updated brake hose helps much in this case as it seems to be more dependant on the leaverage you can put in, that also varies with hand strength of each rider so you may even get some people calling the same brake better or worse if the tried one bike.

[Legin]

Hmm, Starting to get the idea this front brake is going to take me a bit more effort to resolve. Reading around it seems apart from the availability of decent pads (not) the problem could be piston ratios and given I like to keep my bike looking standard even if it isnt then the next step looks like engineering a smaller master cylinder piston into the original housing. We will see.
I think my clutch is just worn out so will strip and replate it at some point, are the EBC clutch pack and springs well thought of ?
Front tyre is some sort of Dunlop antique and the rear is a Avon in good nick, what would be the best front tyre to get BT45 gets lots of mentions.

[Spitfire]

Watch out for the tyres, it's amazing how hard they go with age, mine looked perfect, they were new on the bike in 1994, the bike was then put into storage but by 2004 they were hard as a rock. I'm sure that I read somewhere that you are supposed to replace tyres every four years or so because of this.

Cheers

Den

[Legin]

Turns out my rear tyre is a Continental. Which tyres should I buy ?

[K2-K6]

I've no really current experience of new tyre choice on this bike but many I see have Avon so ideally you'd need some response from some of the others. Use Continental tyres on different bikes and like them, always seem to be accurately made and have not had a bad one yet. Using 750's in the 70's and 80's they always were more neutral steering with things like TT100, Pirelli Phantom as the rounder profile give a much more even / linear progression as you leant over especially more subtle is you start the move away from upright.

That brake point you make is interesting, you can squeeze the standard master-cylinder till your eyes bulge and still not lock it but given a more advantaged ratio at that end they seem to perform quite well at the wheel end so worth thinking about a cunning solution. Think the pads will be less critical in normal running if you could give more squeeze anyway, you'd just have to find out about repeated high temp performance if used at that level.

[Legin]

I sorted the front brake in the end by fitting brembo pads but more importantly cleaning up the caliper bore , seal and piston. Was full of some sort of crud. Brake much more effective now and doesnt drag, its not like a modern of course but good enough for me. I have also made a luggage rack by grafting an NOS rd 80lc one onto the original rear grab, I think it looks better than the ones I have seen in pics but the main reason was i couldnt find one to buy, its painted for now but i will get it plated at some point. Next job Im going to do are the clock faces with vinyl overlays as they have suffered in the sun.
Thanks for the info and welcome chaps.

[UK Pete]

Good luck with the clocks, who/ where are you getting the faces from, is it hear   http://www.clocksndials.co.uk/
I have a set of k2 clocks i am experimenting with at the moment, i have got them apart ok , shot blasted the metal top cover, ready to paint the only thing is the glass is scratched up a bit, so i am not sure wether to put them back together or get a new glass and reface them
Pete

[Legin]

Yes Im getting them from clocks n dials, fortunately mine are pretty fit so with a blast and paint will be ok as the glasses look good apart from a bit of paint on them. The clocks work great so Im a bit nervous about buggering something up. I note my faces are blue is this a USA thing as I was thinking most are green on k1 ?

[kent400]

There will be an article in the next issue of the VJMC magazine Tansha on the subject. That information comes from the editor. The article covers those with the metal bodies and describes how you can remove and refit the band without cutting it. As for the dial faces I've not used Clocks and Dials but Reproduction Decals in Canada carry a very good range and they are of good quality. Their CB750f ones they have are green. The tacho red line seems to vary depending on the exact model so a bit of care on selection is required.

The glasses are are convex, it is possible to get them cut to pattern. I had a batch cut for the smaller 400f instruments which are also convex. Worked out at about a fiver each.