Cb750 frame welding

[Crispy]

Having stripped my K1 frame down and getting it ready for powder coating I'm slightly concerned at the quality of welding and assembly...the welds are quite rough and some welded on sections look as though the welder had had a few beers..? ie: out of square! Is this normal or have I just got a rough one?

[Laverda Dave]

All looks normal to me. The quality of welding on old Japanese bikes was always bad.

[UK Pete]

Yep really bad welding on early honda sandcast no is Awful but they don't fail..rough but strong🤣

Sent from my SM-G930F using Tapatalk

[Crispy]

Well thanks for that!  I feel much better now I know it's normal standard! 

[MrDavo]

When I was strictly a Brit biker we used to describe Japanese frames as 'welded at' rather than welded together.

As Pete says I've never seen one fail.

[Laverda Dave]

Do yourself a big favour and get the frame checked for straightness before you paint it. Its an old bike and you don't know it's previous life, could have been down the road once or twice. You'll need to put the back wheel in the frame and the bottom half of the engine bolted back in place to make a proper assessment. It costs about £70, cheap compared to rebuilding the bike only to find it doesn't steer properly.
The guy who checks my frames told me a lot of frames were slightly out of true when they came out of the factory jigs!

[MrDavo]

When I worked for the Honda Superbike team, the first thing we did when we got a new RC45 frame was to take it to a race shop in Bolton, I can’t remember the name, to get them straightened.

They usually needed quite a tweak, they were all alloy, beautifully welded but the guy reckoned that the heat involved distorted them.

Of course they did get lobbed at the scenery fairly often, so got rechecked a few times.

[Rozabikes Tim]

When I worked for the Honda Superbike team,

Tell me more?

[MrDavo]

1999, RC45s with Michael Rutter and Ian Simpson, we did the BSB season, the TT, NW200 and Ulster GP, there we were under seige because we had Joey on the spare bike.

I’d run away from being an accountant and learned to drive an HGV. I got the job because of my racing experience, so I knew my way round most of the paddocks. Employed originally by Jack Valentine, I was one of the truckies and also parts man, which is where I picked up my fetish for Honda parts books and bags.

Somewhere I still have a confidential ‘do not copy’ parts book for the factory RC45 engine. A Jiffy bag with replacement valves and springs, made from titanium, came with an £8,000 invoice, in 1999!

I worked a couple of seasons in car racing, too, at Heywood Racing we had a teenage Kimi Raikonnen in a Formula Renault for half a season, I think he spoke to me once. He’s still a man of few words.

I gave it all up in the end to stay married,  because of the insane schedules, always being away, everyone else was single or divorced.

Anyway enough of the thread hijack, we were on welding..:

[mike the bike]

Now's the time to clean all the pigeon shit welding up with a linishing disk.

[Spitfire]

We used to joke that the welding was done by a little old lady with knitting needles.

Cheers

Dennis

[Bryanj]

Weren't Honda one of the first to use robot welders

[Crispy]

Do yourself a big favour and get the frame checked for straightness before you paint it. Its an old bike and you don't know it's previous life, could have been down the road once or twice.

That's a good shout! ..the rear footrest / exhaust mount tubing on this frame is not exactly symmetrical although there is no sign of damage, paint flaking etc. Ill just have to rethink the order in which I proceed slightly....but worth it for peace of mind!