Just wondering which size folks use on big twins ... Timesert lengths for an exhaust stud repair, and may be intake manifold?

They say drill to .250" over, .750" (1") seems a like overkill ... would that be .620" on exhaust and .450" on carb side then?

Thanks.

I don't fancy adding additional ventilation to the ports.

 

time serts come in different types - some have a dish on the bottom some stake in place

all that is needed is to clear the sert to the bottom when installed - you dont what it sticking up

heli coil is more than sufficient unless the hole is totally screwed

picture up what you have

 

Are you sure about those numbers???
Heli. Coil would do fine as John mentioned

WP

 

No pictures, I am sorry. I've got 2 heads; one with a now sheered off broken stud (on the easy side). I'm thinking of just re-doing them all to do the job properly.

The studs on the head with broken stud are a shorter length from the other. I think they've been done before as they don't have the same shank (?) between the UNF and UNC threads as the OEM studs have.

Right now, I don't know what I have to deal with but for less than the price of sending them into a shop to do, I could just buy a 5/16th kit.

I appreciate Helicoils would do, and certainly would be cheaper (I see the crankcases are all held together with them), so considering Timeserts is just nicety. And I'll be beating myself up for the sake of $70 or so as a do have access to an 8mm kit - but how could I live with the thought of the guys in the parking lot knowing I had metric sized nuts?

Timesert says,
The sizes are; .350", .450", .620", .750".

Kits (0561) are coming now in at around $66 with 5 x .450" inserts.

 

Do what???
5/16 and 8mm are so close to the same it s unreal
Heli coils come SAE and Metric
The helicoils will take less meat out of heads and do the same job

Hope ya get her fixed

WP

 

It was a joke ... based on the response of an Indy mechanic discovering my bike had a metric nut and bolt holding some parts together.

Obviously you're right that there is, literally, a hair's breadth of a difference between 5/16" and 8mm. Unfortunately the Timesert kits are not interchangeable. Something to do with ensuring the internal and external threads line up.

May be I should just do that but the depth question still remains the same. I figure it's not a high torque part and so if I am going with an insert, I could use a short one (and even a fine thread).

 

[QUOTE=Lucky Luke;14176132]No pictures, I am sorry. I've got 2 heads; but how could I live with the thought of the guys in the parking lot knowing I had metric sized nuts?[/I]

As long as your metric sized girl doesn't care, I don't think it's going to be an issue.......

Just use the HeliCoil.....and just do the ones that need it. Don't fix what ain't broke......

 

You know, normally I'd agree with that philosophy - and have found out why time and time again.

But, in this case, it's all apart and I'd rather do at least the rear ones whilst they are off. I think it's the rear that is broke.

Front I reckon you might be able to do in the frame easly enough.

 

You should be able too.....

 

Measuring up an exhaust stud, it seems the UNC part is about .825", so the hole has to be at least that deep.

Figure if I am using an insert, I don't need the entire length threaded though, or could shorten it. I must admit, drilling an 1" long hole in my head makes me nervous as it has been ported! I am half expecting the bolt to protrude.

Carb manifold plate screw is about the same length but only half screws in.

So what sizes are people using?

Thanks