Author Topic: Exhaust Studs  (Read 288 times)

Offline Johnnyboy750

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Exhaust Studs
« on: February 09, 2019, 10:25:04 PM »
I’m new to all things CB so hopefully this ain’t deemed a stupid question?

I have a 750 K6 which has a loose exhaust stud on one of the cylinders. My question for anyone with any experience of this is, is helicoil suitable repair and if so can it be done in situ?? Also if when I get bike in bits more than one thread needs sorting can any or all of the eight be repaired with the head in place? Also any tips on threading or stud replacement??

Many thanks in advance for any replys.

John.

Offline Trigger

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Re: Exhaust Studs
« Reply #1 on: February 09, 2019, 10:30:56 PM »
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If you have a K6, then it should not have studs  ;) Should look like this with the std pipes off.
« Last Edit: February 09, 2019, 10:37:53 PM by Trigger »

Offline Bryanj

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Re: Exhaust Studs
« Reply #2 on: February 10, 2019, 08:40:07 AM »
Some threads can be repaired "in situ" others the frame gets in the way.

Offline Johnnyboy750

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Re: Exhaust Studs
« Reply #3 on: February 10, 2019, 09:14:05 AM »
Sorry my mistake shouldn't have said studs as its same as the pic.

Offline Trigger

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Re: Exhaust Studs
« Reply #4 on: February 10, 2019, 09:30:19 AM »
Very tricky to do these with the engine in the frame as Bryan has already stated but, it can be done. I have done this before in the frame but, not all of them. I used a old exhaust flange drilled out as a guide, then a long drill and a extension on the tap. You will have to use a helicoil as there is not enough meat for a insurt or it is getting close.

If any of the exhaust flange screws snap while trying to remove, then these are a bugger to drill out.

The problem is that you can't just pop the head off a 750 while in the frame, unless it has a frame kit fitted.

Offline Johnnyboy750

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Re: Exhaust Studs
« Reply #5 on: February 10, 2019, 09:50:02 AM »
Looking at the bike this morning in the garage I can see that it has 5 stainless slotted head tapered screws, 1 stainless Allen key tapered screw and two studs so a general mix and match of non standard items. Until I pull the exhausts off the bike and further investigate the condition of the threads I won't know how many need sorting but as a starter where can I source the correct posi head screws?

Many thanks for all the replies.

John

Offline neat street

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Re: Exhaust Studs
« Reply #6 on: February 10, 2019, 05:37:00 PM »
CMSNL
product number: 9360008022
hope this helps? 1 euro each plus carriage
maybe also available from DS
CB750F
Lambretta SX200

Offline Johnnyboy750

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Re: Exhaust Studs
« Reply #7 on: February 11, 2019, 09:18:34 AM »
That’s great thanks for your help.

John

Offline Johnnyboy750

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Re: Exhaust Studs
« Reply #8 on: February 12, 2019, 03:23:37 PM »
On further investigation of my K6 I have found around 3 threads past their best. One in particular has been loose for so log it has opened the hole out to the extent that a M8 helicoil I got from work just drops straight in.

This level of work is above my skills so looking for a good highly recommended company to have a look at all 8 threads while the head is off and sort it out so the fix is permanent.

Much appreciated for any guidance of company’s who would be capable of this task?

Kind regards,
John

Offline Nurse Julie

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Re: Exhaust Studs
« Reply #9 on: February 12, 2019, 03:46:29 PM »
Have you got the engine out yet John?
Im a Nurse, trust me, this won't hurt.....much !!!

LINK TO MY CB400/4 ENGINE STRIP / ASSESSMENT AND REBUILD...NOW COMPLETE
http://www.sohc.co.uk/index.php/topic,14049.msg112691/topicseen.html#new

Offline Johnnyboy750

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Re: Exhaust Studs
« Reply #10 on: February 12, 2019, 05:47:02 PM »
Nope it’s still sat in frame. I can have it in bits over weekend easy enough and happy to rebuild afterwards just hoping someone has a good source who can supply a good service.