KR-1S.co.uk Forum

For the past week I've been tarting up my Kr1, mending fairings for re-painting, tidying up my wiring, sorting out my front indicators & re-plating a few nuts & bolts that have needed doing since day one really.

Anyway, I re-plated the bottom yoke bolts (Kr1 so just the single bolt), polished them up so they're nice & shiney, popped a bit of copper slip on them, tightened the left one to its correct torque value, then started tightening the right hand side then it all went wrong

The bolt has stripped the thread inside the bottom yoke

I didn't get anywhere near the right tension

So my question is......... what's the best way to sort this problem? Do I have enough ally to pop a heli-coil in it or is there a better way of rescuing my bottom yoke? I'm assuming I will have to enlarge the outer hole in order to fit a heli-coil?

I have a spare but the bearing is kaputt & it was only a couple of years ago I renewed the race bearings on the one fitted

On the bright side I suppose its better it happened now than when I next go out on it eh?

Howie,
Not sure about a kr yoke but on a 1s the bolt holes goes right through the yoke with the thead at the back (if that makes sense) if the same on a kr could you put the helicoil in the back, i think they work both ways. will save you opening the outer hole up.

That's an idea 375, TBH i can't remember if the threads go right through on the Kr1 or not

I'll have a look in the morning, fingers crossed [-o<

That's a bugger but did the replating alter the thickness of the bolt ?
I had a mate replate some bolts once and they wouldn't go into the original threads anymore
Had the bolt fully seated or was it just spinning at the beginning of the threads ?
I actually have 4 KR1 bottoms if you need one for sheckles

Thanks for the offer HC, I have a spare bottom yoke but I'm just a bit gutted that I replaced the bearing on the one I have in only a couple of years ago, the bearing looks ok on my spare but grrrrr, just annoying more than anything.

I always strip the plating from the bolts before I replate them because I've heard stories of people having to hammer replated bolts through bearings because the plating was applied for too long

Easily done though. I remember when I first started replating stuff & left a few bolts in & went for dinner. Totally forgot about them When I fetched them out about an hour later, they looked really good but unfortunately two of them were suspension linkage bolts & would they fit through the bearings/sleeves?

Would they f***

Lesson learnt

To answer your other question, the bolts screwed in hand tight fine, it was just as I was torque-ing them up that the bolt slipped in its thread. My torque wrench is not to blame as its pretty new & its Teng. I just think its the thread in the bottom yoke is tired & its the relatively soft aluminium thats given best?

I'm just hoping that 375's suggestion can be done but like I say, I can't remember if its a blind fixing or not

hi howie how do you remove your old plating on the bolts acid or blasting, i had this problem not happy with plating and i just blasted them but only quickly therefore leaving plating on threads, now im back on the ACID then a blast to clean them up then plate comes out great give most bolts a quick try with a plated nut or a stainless one job done

tescr500 wrote: now im back on the ACID

Ah, that explains a lot

tescr500 wrote:
now im back on the ACID



Ah, that explains a lot

Well I've finally come to a decision, after a closer look that is! This is what I spotted..........

[img][img]http://i800.photobucket.com/albums/yy28 ... /018-3.jpg[/img][/img]

What you are looking at is a .40 feeler gauge quite loosely put into the crack on my bottom yoke
Never seen this happen before & like I said, the plating on the bolt in minimal & it is the original bolt(you can tell by the turned over edges ). Pretty glad I spotted it now & not out on the road

In answer to tescr500 question. First I remove all traces of crud/oil/copper grease etc using a parts cleaner. Then I take the cleaned bolt & pop it in brick cleaner (hydrocloric acid?) for ooh approx 30mins to an hour (that will remove the original zinc plate alright!), then I take it to the wire brush on my pillar drill & won't stop till I get a shiney finish. Then I give it a quick clean with a flash cleaner like brake cleaning fluid (make sure you use clean rubber gloves so you don't deposit any oily skin fluid on it for this last stage)

Then into the electrolyte for 20-30mins

Don't use a yellow/gold passivate on any bolts you can see on the finished bike because they just don't look right IMHO

Not seen that before, Possible to clamp it and then weld ? or you going to fit a spare.

wow never seen that either just a dodgy one or been hit at some point i'd change it personally wouldn't bother getting it welded.

Yep, I'd bin that one as well.
Also, is that a toothed washer I see between the clamping faces?

Nope thats just a build up of crud from our lovely British summertime weather & my inability to clean anything properly

I will bin the yoke, don't think I would ever trust it even if I did have it repaired.

Ho hum

That's for the scrap ally bin that mate.

I've never known a replated bolt cause any problems.

before you bin it, take out the stem

i rekon that was cracked years ago ,if u bin it get a chisel and break it away from the meaty bit of the ally ,i bet its dirty , ide repaire it (if needs must) probably take 85 mins,i always clean threads out with a used tap in a battery drill on a lowish torqe setting ,just to clean the factory locktite stuff n any powdercoat or tother muck out before rebuilds,not on thread but some people have never heard of antifrieze ,water jacket was cracked 3" ,it was a kdx so i had to do it,what would a proper bike shop charge for a 3 hour turnaround of strip, weld, rebuild ,and delivery

£80 or more ,or less