Full Suspension Front Triangle Swap To Increase Frame Size?

[benny.c]

My son has a Nukeproof Mega TR in small which he loves. Only problem is he’s grown about 5” in the last year so it’s too small for him now really. He’d like another Nukeproof but I don’t fancy shelling out £1K+ on a Reactor (modern TR equivalent) whilst he’s still sprouting. I could sell his bike and buy another TR but there are not many for sale and I’ve spent a few quid getting his just right.

I’ve seen a NOS Mega TR front triangle in size medium for sale for £100 which would seem to be a cheap way to move up to the next size frame. But is this even possible? I’ve looked at the frame geo charts and the chain stay seems to be same size so can I just swap the small and medium triangles over or will there be differences other than the triangle that gives the bike it’s size? I’ve searched on forums and found a few posts regarding triangle swaps but they tend to just be to replace damage. Any advice welcome!

[DaveyBoyWonder]

Chainstay lengths should be the same regardless of frame size so they should swap over. The slight issue might be seatstays as they'd in theory be longer from the rear axle up to a point higher up on the bigger sized frame than the smaller one but then I'd suspect as a cost saving measure, rear ends would be exactly the same across a range of sizes...

In fact, looking at pictures of TRs, the bigger frames seem to have extended seatposts and an extra brace to the top tube - the point which the seatstays join the shock linkage looks to be in a VERY similar/identical point (level'ish with the top of the back wheel). I reckon the rear ends could be swapped with fronts...

[benny.c]

Thanks. That’s the conclusion I came to also. I might give it a go….or see if his current bike will do until after Christmas and hopefully he’ll be big enough for a large by then.

[bobbo89]

If it's the one on eBay it's got a 'Make Offer' option and given it's an older frame and a bit niche now I'd throw a low ball offer at them and see if they bite. Looks like a shop too and so chances are high that they'll take it just to clear stock.

I'd say it'll work too as the chain stay length is consistent across all sizes and so for the suspension to work as designed and give the same amount of travel regardless of size, the seat stays would need to stay the same.

[lufbramatt]

Exploded diagrams on the Nukeproof website:

https://nukeproof.com/pages/technical-support-docu...

I'd drop Nukeproof a email and see what they say.

Edited by lufbramatt on Thursday 28th September 11:34

[benny.c]

Cheers both. Yes it’s the one on eBay - not going to be in big demand as you say so I’ll take a punt I think.

[bobbo89]

I'm 99.9% certain it'll work, all the size differences are in the front end which essentially just gets longer tubing all round but with bigger shock and pivot mounts to bring the mounting points into the same place across all sizes.

[benny.c]

I’ve gone for it - agreed on £80 posted. If it doesn’t work it will be nice wall art

[benny.c]

The new front triangle arrived this morning. All pivot positions are identical to the smaller frame

[bobbo89]

Winner! Was certain it would.

[benny.c]