1982 CB750k Cut Frame

They have hacked it. If you are in Ontario that may not be repairable. Old frames are welded into a solid structure. Trials Rider may be along soon, old Ontario biker, but I think he will agree that the frame is NFG.

As woodsman said that has been hacked.
Some frames did come with a removable section to make the removal of the engine easier.
You could get that welded back together with slugs in the joint to reinforce when putting it back together.
Either that or cut the correct overlapping joints off of another frame that have them as standard and have them welded in.

Either way as it stands its dangerous and i would be pissed off to find that on a bike i had just bought.

The PO put possibly cheap, off-shore, wrong sized bolts, washers and nuts for spacers on the original removable frame rail.

Is your frame safe now? <- depends on how rusty it is on the inside of the non-rustproofed frame tubes, and if those bolts were ever strong enough to be used where they were used, which is unlikely considering the tubes appear to have been bent to some extent.

Did you get scammed? <- if you paid more then about 800 bucks for a non-running 1982 twin cam CB750 you certainly did.

Add that to the list of things I didn't know.

Thanks for the replies everyone, I'm relieved it wasn't hacked up by the previous owner. Still, it looks like I need to drop the engine, realign the bent frame section, paint, and replace the nuts/bolts. Do you guys see any issues trying to straighten the frame back out? I'm concerned trying to bend it back so things line up will cause structural weakness and could be a safety risk.

Cheers

TrialsRider said:

The PO put possibly cheap, off-shore, wrong sized bolts, washers and nuts for spacers on the original removable frame rail.

Is your frame safe now? <- depends on how rusty it is on the inside of the non-rustproofed frame tubes, and if those bolts were ever strong enough to be used where they were used, which is unlikely considering the tubes appear to have been bent to some extent.

Did you get scammed? <- if you paid more then about 800 bucks for a non-running 1982 twin cam CB750 you certainly did.

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Thanks for the reply, I'll be trying to fix things as I mentioned in my other comment. I paid about $2000 CAD so $1580 USD, but it's a complete bike with a clean title and runs well.

Get it plated asap and do your modifications after. Just make it look nice and stock and un rusty before the mechanic sees it to certify it.

and get the right size bolts, that's easy.
How much is insurance going to cost you?

TrialsRider said:

Get it plated asap and do your modifications after. Just make it look nice and stock and un rusty before the mechanic sees it to certify it.

and get the right size bolts, that's easy.
How much is insurance going to cost you?

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Roger, I'll get it cleaned up. Are you saying don't worry about trying to straighten the frame?

I was able to get my '05 CBR 600rr insured for about $300/year, and my dad went with the same provider for his '79 CBX1000 at about the same price. I'm assuming it will be in that range.

He also didn't have to get an inspection when registering/insuring his CBX, as the bike was last registered in Alberta. Same case for my '82 CB, so I'm hoping I won't have to have a mechanic certify it. That being said, I want to ensure it's safe to ride before I take it out.

Holy you get good rates, good luck with not needing a certification. I don't think it's badly mangled, the paint will likely crack or flake off anywhere that is damaged bad. It's not a pretty frame.

My minimal insurance coverage on 2 bikes ~700 and 800.
Dirt bikes don't need insurance, so I can have any number of those

TrialsRider said:

Holy you get good rates, good luck with not needing a certification. I don't think it's badly mangled, the paint will likely crack or flake off anywhere that is damaged bad. It's not a pretty frame.

My minimal insurance coverage on 2 bikes ~700 and 800.
Dirt bikes don't need insurance, so I can have any number of those

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A friend just paid 840 for 3 which I didn't think was too bad.

You know I got thinking; I bet there was a crash bar bolted to that frame connection and it got crashed. Chances are that's why the bolts are so long and it has some weird bend damage.

Crash bars save one thing and damage another.

TrialsRider said:

You know I got thinking; I bet there was a crash bar bolted to that frame connection and it got crashed. Chances are that's why the bolts are so long and it has some weird bend damage.

Crash bars save one thing and damage another.

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I bet that's what it is. The bike has signs of being laid down on the right side.

The frame is cheapest 'mild steel' Honda could find at the time so don't worry about bending it back into shape.
The chances of frame cracking are pretty slim, they usually crack from long term engine vibration but more often will rust out long before that happens particularlyu around top of rear shock mounts where they flex
AFAIK, all the twin cam 750/900's had removable frame section to remove engine (bloody heavy lump as well)

It's a Canadian bike, some were kept in heated garages their whole life,
others left out in a snow bank for one winter, the frame will crack anywhere it can fill with water.

It's hard to see from the photos but if you think the sub frame piece is bad, they are available cheep enough on e-bay ($7-$30 dollars) also You might look for misc. hardware or left over bolt kits to find the rest. The only one that might be real bad is the inside plate, this one is threaded and if the threads are bad it's probably best to get a good one. The shipping (US) is cheep, it might be more in Canada? I don't know how picky the inspectors are for you, we don't have to do this in California. I can't see how they would expect the paint to be perfect on a 40 year old motorcycle without touching up? The DOKC 750s are heavy but they are a little faster, also the parts are mostly interchangeable so You can make it look any way you want. Mine is a '80 750C and I switched out the Comstar wheels out for spokes because I like them better? It's not a "cafe" but it's a great commuter and I ride it more than my others because it's rock solid and dependable.

Also, I think these particular frame parts are the same on all the DOHC 750s , I think the 750c parts are the most available and cheapest?

Shipping to Canada has gotten crazy expensive compared to internal shipping in USA.
Still cheaper than 'international rates' to ship everywhere else in the world though.
Last time I sent medium flat rate box to Britain it was $48.00, in USA it's under $16.00

crazypj said:

Shipping to Canada has gotten crazy expensive compared to internal shipping in USA.
Still cheaper than 'international rates' to ship everywhere else in the world though.
Last time I sent medium flat rate box to Britain it was $48.00, in USA it's under $16.00

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Shipping to the USA from Canada is still cheap and easy for items under about a grand isn't it?
It certainly should be.