Topic: will hm341 stock pipes fit on a 1969 cb750?

[ChortlingSandcaster]

I believe the hm341 pipes are for the K2 model and not the K0 model.
But -- will they fit my '69?

[myhondas]

But it begs the question.....why would you.....there are 300 pipes available and the sound difference itself would make you want to keep the originals. right now there are a number of sandcast owners ordering  pipes the the sand cast only owners forum.....you might want to check it out.

[754]

 They will fit but if its early the flatspot for the rear brake is a 5p foot giveaway, that it is nor cirrect..

.. and if its under # 1220ish the un numbered pipes mounting area is narrower and needs shorter bolts like the early one I had did..

[ChortlingSandcaster]

But it begs the question.....why would you.....there are 300 pipes available and the sound difference itself would make you want to keep the originals. right now there are a number of sandcast owners ordering  pipes the the sand cast only owners forum.....you might want to check it out.

hows $50 not $1200 sound   

The 341 mufflers/heat shields look IDENTICAL to the hm300s anyways.
So even though I'm not a 'perfect purist' I'm still a 3/4-purist I reckon, so's if
they look the same why not save $1150.

[754]

 Actually the 300 series heatshield have a different background  than the 341 shields.. but at 50 bux grab em..



 300 are satin coloured not black

[ChortlingSandcaster]

Actually the 300 series heatshield have a different background  than the 341 shields.. but at 50 bux grab em..



 300 are satin coloured not black

Okay, thank you.  Btw will the 341s bolt right on to my '69?  Or do I need to alter something,
like -- spacers or bolt lengths or sizes, or brackets or ....?

I have read some older posts and noticed that the 341s are 'more restrictive' but could find nothing that says "the 341s bolt right on to a '69 bike."

[Johnie]

I think you would have to rejet the carbs with the 341's. I saw that on this board. But I guess to rejet and use the 341's would be alot cheaper for sure. Of course, maybe that 69 has the incorrect era carbs on there and you won't have to rejet. Do you have the 4 cable carbs?

[ChortlingSandcaster]

I think you would have to rejet the carbs with the 341's. I saw that on this board. But I guess to rejet and use the 341's would be alot cheaper for sure. Of course, maybe that 69 has the incorrect era carbs on there and you won't have to rejet. Do you have the 4 cable carbs?

I just checked it, I see some sort of pulley-like deal with 2 throttle cables attached to either end of the pulley, one cable to 'pull' and the other cable to 'push' I guess?  Then on top of each carb cap there's a extra little metal box and they're all connected (it looks like it but the bike is in the garage surrounded by other bikes and its a bit hard to see).

Someone help me out here!  I thought that the sandcast bikes all have a different cable to each carb cap and this pulley arrangement came in soon after.

Just so you can better help me on this carb issue, here's the numbers from my bike:

ENGINE #:  CB750E-1003334
FRAME #:   CB750-1003278

And someone called my attention to a set of numbers I had not noticed before,
'Swoop' said:  "If you look in from the kickstart side....on the top case....just in front of the rear top securing bolt you should see 3 or 4 numbers.These are casting dates on the early ones....not sure how long they continued."

I FOUND THE SET OF NUMBERS HE WAS TALKING ABOUT - it says "6-25"

I was expecting to find a different cable going to each carb?!!!


WHATS GOING ON HERE.

[ChortlingSandcaster]

Let me add one more thing.

This '69 750 came with a 4-into-2 Hooker header and it looks OLD.  The style of it is just nothing I ever saw in a 4-into-1 or 4-into-2 and I have owned Honda fours since my very first 1976 cb400f my dad bought me in '76.

So I guess its possible he (the prior owner) swapped in newer carbs for the pipe?   Because the carbs have old individual air filters on them too.  Maybe he did the carbs up for that Hooker pipe.

[754]

 Yours has been switched to later carbs..

 Some of the early ones, in the lower number range, have a  number cast in the carb tops, you need them to be correct, they are being repopped for 400 + I think.. just the tops and rings..

 You dont have to change carbs just for a pipe. Some changed cuz they felt they stayed in adjustment longer..

 I bet your 4-2s are the same as a buddy has on his 72
 I bought several Hooker pipes new in the early 70s

[Duke McDukiedook]

There are different variations on the 341 even- 5 and 7 chamber.

[Johnie]

Yup, if you have the push pull throttle end then someone swapped them out for 71 - 76 model carbs. The only way to tell if you have the correct jets is to look on the top of the carb casting and you will see a number like 657B or something like that. With that number we can tell you the correct jet sizes you should be running with the 341's. So do not buy those 4 cable carb throttles you were looking at. Last, I have attached a couple pics for you. The first is of the 69-70 KO carbs with the cable on each top like you mentioned. The other is probably what you have the later model carbs. Let us know how you come out.

[Johnie]

Here is a pic of where to find the carb ID that I spoke about. Click the pics to enlarge...

[zzpete]

I used to have a 1969 and it had HM341 pipes.