Mag fron to spoke conversion

[WPGxs650_brat]

To start I have a 78"

I started with a stock 19" mag, and now have a 19". Same years, caliper and brake all line up perfect.

That said, the bolts for the caliper (off of the mag wheel) are too long.

Does anyone know what the proper bolt size (more important length) is for a 78-79 fron spoke wheel?

 

[5twins]

The caliper is the brake unit itself and mounts on the fork leg. I think you mean the brake disc? According to the parts diagrams, '78 spoke and mag wheels use the same disc mounting bolts. But, are you sure your "new" spoke wheel is a '78? Older wheels that were used with the earlier disc style used shorter disc mounting bolts. The mounting holes in the hub were "blind", they didn't go all the way through. Check your hub for that.

 

[Beags64]

Just checked some I had on the bench
'77 spoked hub (w/blind holes) - 23mm
'78 mag wheel - 30mm

 

[650Skull]

If it was me i would make sure the bolts screwed into the hub and if i found they were to long then cutting a few mm off the end should remedy that problem..........

Or you cold find out the thread pitch, bolt length and go and buy another 6 bolts the right length..........

 

[WPGxs650_brat]

I was told the spoke hub is the rite year.

And I'm aware of the 3-4 different hub and caliper sizes. The caliper and brake all lines up bang on when on the forks.

I

Just checked some I had on the bench
'77 spoked hub (w/blind holes) - 23mm
'78 mag wheel - 30mm

I thought (I know lol) 77' didnt line up with 78/79 hub/brakes. But those numbers jive!

Thanks! Everyone!

 

[XSLeo]

You measured the holes in your hubs. The difference is 7 mm.
The bolts you re trying to use came from the Mag hub, right?
Take one of those bolts to a good hardware store. Look through the metric bolts for some the same diameter, same thread pitch but 7 mm shorter. Buy as many as you need.
My local TSC has a good metric bolt selection, so does Lowes. I don't have a Home Depot close by but they probably have a good selection.
Leo

 

[5twins]

I don't think you'll find 23's but you can sometimes find 22's. That's what I'm using (in stainless).

 

[XSLeo]

I like the button head Allen's. They don't stick out a far as regular Allen's or regular bolts. A bit of lock tight you don't need the stock lock tab plates.
Leo

 

[650Skull]

Seriously...........Cut the bolts to length, LOL.....Saves time and money

 

[WPGxs650_brat]

Seriously...........Cut the bolts to length, LOL.....Saves time and money

I'm with you, but more curious to the actual measurements. As too many sites advertise as "fits all years" and that's complete BS lol

 

[650Skull]

You have the different bolts.........you know they don't interchange...........That is now the truth..........