Floating rotor bobbins needed! UK Friends?

[mikey]

AP Racing CP2494-504K12L (qty 3)

I can't seem to find anyone with the AP kit (number above) which includes the bobbins, bolts, washers and nuts. TMS motorsports in the UK listed them in stock on their website so I placed an order there and then got an email saying they are refunding my card because they don't have them. Essex in the US never replied to my email.

I haven't found any other bobbins that match the AP style I need. If I could source even just the bobbins (CP2494-504MP) qty 32 needed, then I can buy bolts, washers and nuts from Pegasus.. Page 45 of the AP catalog shows the details for the bobbin CP2494-504MP.

Anyone got a source? Anybody in the UK that can help with the search and maybe buy more locally and then mail to me?

UPDATE - DISREGARD. OVERCOME BY EVENTS (WON'T FIT)

Mike

[Garey Guzman]

Maybe call Primus for ideas? Brad sells AP stuff so maybe he can help?

[greg pizzo]

When do you need them ?

[Banger Rally Man]

Listed as in stock


https://www.questmead.co.uk/Categori...unting/Bobbins

[mikey]

thanks guys.. scrap the request though.. after some re-measuring the AP bobbins aren't going to work. Glad my order got canceled after all. Although they look the same, the slot width in my rotors is .370" or 9.39mm versus the 9.40-9.45mm width of the AP standard bobbins.

Beating my head into a wall now. Had I realized this I would have had the slots made the proper width for standard AP bobbins. I'm told I need 0.015" clearance. Off to the machine shop I go (remotely, via email and phone as usual).

[Garey Guzman]

thanks guys.. scrap the request though.. after some re-measuring the AP bobbins aren't going to work. Glad my order got canceled after all. Although they look the same, the slot width in my rotors is .370" or 9.39mm versus the 9.40-9.45mm width of the AP standard bobbins.

Beating my head into a wall now. Had I realized this I would have had the slots made the proper width for standard AP bobbins. I'm told I need 0.015" clearance. Off to the machine shop I go (remotely, via email and phone as usual).

Oh lordy, I sure hope this car is SPECTACULAR to drive after all you're going through!!

[tlracer]

Mikey - so the slots on your rotors is 9.39mm and minimum on AP rotors is 9.40mm?

If you need 0.015" clearance, that is 0.381mm.

I'm not sure the 0.01mm slot difference is a deal breaker..?

Addendum: Just had a look at AP's drawing and realised I'd misread your post. Nevertheless can you not increase the clearance on your new rotors?

[mikey]

Oh lordy, I sure hope this car is SPECTACULAR to drive after all you're going through!!

Yeah me too! I'm sure it will be a blast and it's way too hot in FL right now so I've got a couple more months to sort everything. I'm learning a lot so not all is lost.

Appreciate all the support the community has provided through all this, I'm learning a lot more about our members and all their capabilities!

[mikey]

Mikey - so the slots on your rotors is 9.39mm and minimum on AP rotors is 9.40mm?

If you need 0.015" clearance, that is 0.381mm.

I'm not sure the 0.01mm slot difference is a deal breaker..?

Addendum: Just had a look at AP's drawing and realised I'd misread your post. Nevertheless can you not increase the clearance on your new rotors?

AP Rotors likely have a slot width of 9.50mm. Their bobbins are 9.40-9.45mm wide. My slot is narrower than the bobbin (won't slide). So not enough clearance for the way my rotors were made. Yes one solution would be to send the rotors back and have the slots machined wider, but either way I need new bobbins because the ones I have do not give the proper float (too short).

Talking with the machine shop, doesn't sound like it's too hard to just have the bobbins made to my spec. If it's crazy $$ then I will look at widening the slots instead as you suggest so I can use standard AP bobbins.

Couple different forum members have reached out with the capability to make bobbins so I think we'll have a solution soon!

Cheers,
Mike

[tlracer]

Hi - yes, I'd initially misread that the AP rotor slot was 9.40-9.45mm, not the bobbin width.

Getting new bobbins cnc'd shouldn't cost a lot. I have a great guy over here who produces stuff at fantastic prices for me.

Once the car is finished, all the stress will be worth it!

[mark elder]

Hi - yes, I'd initially misread that the AP rotor slot was 9.40-9.45mm, not the bobbin width.

Getting new bobbins cnc'd shouldn't cost a lot. I have a great guy over here who produces stuff at fantastic prices for me.

Once the car is finished, all the stress will be worth it!

If it was me and the bobbins were CNCed, I would get a whole spare car set made plus 2 more. They wear out or worse, you drop one in the grass and you cannot find it. I think in an ideal world a new disc deserves new bobbins (and nuts) unless you are trackside and have no choice.

[tlracer]

Mikey - I've just been going through this again along with your separate thread with the new Coleman discs:

Were the discs supposed to be a direct replacement for the AP ones, in terms of mounting onto bells?

To enable you to use the standard bobbins, the new discs need machining to exactly copy the dimensions of the AP ones? Specifically a slight reduction of the mounting flange thickness and widening the slots.

A better plan than "one off" bobbins?

(Yes, I know that's the opposite of my earlier post )

[mikey]

the challenge is that getting standard AP rotors to fit with my specific uprights, wheels and pre-existing rotor hats put me down the path of Coleman rotors made to copy the ones that were on the car (unknown brand) and just fix the offset issue. But the flange spacing and thickness was just matched to what I had, which I've realized are not AP standard and also that the bobbins I have were never long enough to achieve proper float.

If I had studied page 36 of the AP catalog more before hand, I might have ordered a set of CP4448-410/1 rotors and see if they would work with my hats, but they are listed as bolted, not floating rotors so probably not for me. 276mm is really what I needed and got from Coleman, but 280mm is the size I wish would work because then I definitely could have gotten all AP standard stuff to match. Just no way to get the proper clearances, I'm on the edge of what is allowable per AP and Brembo engineering drawings already.

It all seems to stem back to the fact that this car arrived in North America sans brakes and engine, but it had brake bells/hats bolted to the hubs and the prior owner just made stuff work to the best he could for him.

When I'm done sorting, it'll be much easier to get the consumables going forward, but certainly could have engineered differently to use some other AP parts. Coleman prices are good though, so not a big deal other than the lead time can be a few weeks.

Bobbins should last a long time - I will probably get a spare set as suggested.

altogether, the next owner after me will hopefully appreciate how well sorted this is now! if I ever sell it, in 30 years from now LOL.

[fkennette]

Coleman has Bobbin kits,
http://www.colemanracing.com/Drive-B...Kit-P3603.aspx

Is that what you're looking for? I used them as replacements on a Mygale and they worked fine.
Francis

[mikey]

Coleman has Bobbin kits,
http://www.colemanracing.com/Drive-B...Kit-P3603.aspx

Is that what you're looking for? I used them as replacements on a Mygale and they worked fine.
Francis

Thanks - those don't work for my setup. Glen and I did look at that.