Author Topic: Hi! (Read 2871 times)

jonbuoy · « **on:** January 11, 2007, 08:55:18 PM »

Hi, just got pointed onto this site from a New Zealand biker site. - Great looking site by the way. I want to do a CB750 or similar as a Cafe racer - I think I have a donor bike here picked out. Its a 78 750 Supersport SOHC. I only have two concerns with it - the first is a bearing rumble/squeal in neutral - clutch in or out. It seems to be coming from the left hand side of the engine, and almost disapears when I put the bike into gear. The second problem is the head gasket looks to have an oil leak. I'm not so worried about the gasket as I've done them before (not on one of these though...) the noise does bother me a bit though. Any ideas as to what might be causing this?

Other than that the bike is pretty tidy for 20+ years old. Thanks in advance.

seaweb11 · « **Reply #1 on:** January 11, 2007, 10:11:51 PM »

Welcome:
You won't like this.....but you will have to pull the motor to do the head gasket

jonbuoy · « **Reply #2 on:** January 11, 2007, 10:30:23 PM »

Ah so even if it is something more serious motor would be out anyways. Maybe I'll just make a silly cash offer on the bike and get my hands dirty....

seaweb11 · « **Reply #3 on:** January 11, 2007, 10:57:58 PM »

dig in

burmashave · « **Reply #4 on:** January 11, 2007, 11:26:14 PM »

Welcome, jonbuoy! I won't weigh in on the noise, but good luck on getting started. If you haven't already, you may want to check out the Bike of the Month Thread. I think all of the winners are astounding, and a large bunch have been cafe's.

750goes · « **Reply #5 on:** January 11, 2007, 11:31:56 PM »

If the noise sounds like it is coming from the overhead cam area - be wary - it could be a very dry cam tower ready to cry like a banshee IF the bike has been sitting for a very long period... otherwise pull out the large screwdriver/stethoscope and try and find the source of your grinding noise...

turtle · « **Reply #6 on:** January 12, 2007, 12:08:59 AM »

Hi jonbuoy. If you are another Kiwi, watch out for Terry from Australia.

eldar · « **Reply #7 on:** January 12, 2007, 12:05:21 PM »

dont worry about them aussies. He is just alarmed the the 78s are growing!

750goes · « **Reply #8 on:** January 12, 2007, 03:02:59 PM »

eldar,

keep growing - Yes I think that's right - if you keep them in a dark room, feed them BS -

they thrive (oh sorry thats mushrooms)

K8's are a bit like Leyland P76 cars - we used to call them P38's (they had a V8 motor that had very low power) not a real car, just half a car...

Killer Canary · « **Reply #9 on:** January 12, 2007, 07:36:44 PM »

And so it begins.

burmashave · « **Reply #10 on:** January 12, 2007, 09:17:14 PM »

Quote from: Killer Canary on January 12, 2007, 07:36:44 PM

And so it begins.

That implies that it ended at some time before.

And 750goes, I resent the fact that you think I should be fed to the '78's.

-BS

jonbuoy · « **Reply #11 on:** January 12, 2007, 09:36:32 PM »

OK I didn't buy it - test ride went fine - nice bike to ride. I'm pretty sure the majority of the noise was cam chain and clutch area. I was just about to hand over some money when I noticed the oil light flick on when it was on the side stand - there was still oil in the header tank so I don't think it was just low on oil - thats kind of what the owner was telling me. On the centre stand it didn't seem to come on - he did mention it had flicked on before at idle - at least he was honest. I ended up walking away, guess I'll keep looking. I think the CB range would be perfect for the conversion - they look so right when done nicely. I will wait for another to come up.

Cheers

John

750goes · « **Reply #12 on:** January 12, 2007, 10:54:17 PM »

Oil light flicking on at idle does not mean squat - if it goes out when you lift the revs all is fine

cam chain adjustment - no real problem there either
rattly clutch - tell me who hasn't had one at some time or other - there are fixes for that...

BS - sorry I used your initials I obviously did not think of using your name in vain - I will consider your feelings everytime I use the expression mushroom

sorry - no disrespect intended if thats what came across.

killer canary - what begins --- oh life past 40 - -yeah thats me

eldar · « **Reply #13 on:** January 13, 2007, 08:52:57 AM »

You would have to be referring to the k4 if talking about low power. Course no one wants to admit that the cb came full circle with the k8! 69-good power, to the 78-good power and most reliable.

750goes · « **Reply #14 on:** January 13, 2007, 01:36:04 PM »

eldar,

think of this

head over toilet bowl uttering the famous words RRRRRRRRRUUUUUUUUUUUUUTTTTTTTTTTTTTTHHHHHHHHHHHHHH

ALL SOHC's are great

dagersh · « **Reply #15 on:** January 13, 2007, 04:23:39 PM »

Jonbuoy,

I would go take another look - maybe he will even drop the price. If you are pulling the engine anyway, all may be good in the end!

Great luck!

Gersh

jonbuoy · « **Reply #16 on:** January 15, 2007, 11:36:49 PM »

Good advice! I bought it in the end for a good price. Its a 750F with a 750E engine. Compression is a bit on the low side (115-125 - cold) but I'm going to pull the head off anyways to do the oil seals. I will check on the bore and valves when I get down that far! Thanks for the advise everyone.

TomC · « **Reply #17 on:** January 16, 2007, 06:16:08 AM »

Hi Jonbuoy
"Good advice! I bought it in the end for a good price. Its a 750F with a 750E engine."
I assume that by 750E engine you are referring to the engine number. Some of the engine number lists show 750F in the engine number of the F or SuperSport 750s. My F1 has shows 750E. No one on this group has seen an engine with 750F in it.
TomC

Rushoid · « **Reply #18 on:** January 17, 2007, 12:20:58 PM »

Hey Jonbouy! Welcome!

I think all of the engines are 750E. If your going to take parts off, don't forget to share them with your SOHC brothers!

How 'bout some pics?

News:

Author Topic: Hi! (Read 2871 times)

eldar

eldar