Why the loooong chain tensioner bolts? my first mod

[JeffK]

Just got the Brammo from the dealers.
One of my first "modifications" will be swapping the two inch chain tensioner bolts for shorter allen bolts.
Why Brammo fitted such long bolts is beyond me..

Shorter ones will save weight too, extend range

OK so this is what they look like, straight from the shop. (no not that dirty, but got home in a rain storm)



Tried some 40 mm first:


Then some 30mm bolts:

[JeffK]

Yes, that looks good (at least to me)
and it saves 20 grams of unsprung weight. 

[frodus]

You don't have much more room for adjustment there with the smaller of the three. I'd go with the middle size.

[JeffK]

You don't have much more room for adjustment there with the smaller of the three. I'd go with the middle size.

Yes, looks like that, but there's still 4 full turns to adjust, and with the chain oiler installed, I do not expect to adjust more than half a turn each year.
So that will be 8 years of adjustment.

I expect to trade in the Empulse before that..
Considering the developments in EVs, there will be quite a few new models to choose from by then.

[Roland Stone]

Curious to know, - did you loosen the axle nut to change the bolts or just replace them with the axle torqued up?

Also, what is the size and pitch of the bolt?

The shorter bolts do look a little less conspicious!

Roland Stone

[JeffK]

Curious to know, - did you loosen the axle nut to change the bolts or just replace them with the axle torqued up?

Also, what is the size and pitch of the bolt?...........

No need to loosen the axle nut, Roland.
Just undo the locking nut and take the bolt out.
Put the nut on the new bolt and screw back in, just hand tight, as is is only an adjuster bolt.
Then lock the bolt in place with the locking nut.

Most bolts on the Empulse are standard Metric. (available in every hardware store in Europe)
The ones I used are 30mm. M8 (8mm thick, 30mm long, standard 1.25 pitch)
The long Brammo bolts are made from A2 stainless, but I do not like to use those with the other galvanized parts. It seems to make other parts rust faster, and I like to ride trough the winter (salt etc)

[Roland Stone]

The reason I asked is because on my Bonneville the "book" actually tells you that after a chain adjustment you should tweak the adjustment bolts 5 foot pounds after torquing the axle nut.  Someone on the Triumph Ratnet forum finally asked why (God doesn't have to explain) and the consensus reasoning seemed to be that the adjustment bolt actually helped maintain (backup) the set chain adjustment.  Some respondents replied they actually noticed loosing chain adjustment soon and sooner if they didn't do the 5 foot pounds torque(?).  I never noticed but always torqued 'em up anyway.  Although I didn't do an actual torque of my Empulse bolts, with the Triumph procedure knocking around in my head, I did put just a sligjt twist to the bolts after doing the axle.  Was thinking if I just pulled my Empulse bolts out to replace, I might by some Triumph voodo affect my chain adjustment.  If there's anything to it, maybe it's because the Triumph adjusters don't have lock nuts like the Empulse set up.  Apples and Oranges.........

So anyway, what I actually wanted to confirm, - are your replacement bolts galvanized then?

[JeffK]

No, not galvanized,I used the wrong word for it, the bolts are zinc plated, like all the other bolts and screws on the Brammo.