GPI Racing Radiator

Hey folks,

So I read some of the positive reviews of the Chinese radiators out there, and GPI racing seemed like a good one to start with. I've got a 2001 DR-Z400S and the right-side radiator was mashed by the previous owner.

I received mine today, and started the installation. The left-side radiator went on easily enough, although the tabs for the fan wouldn't fit properly. I just straightened them out and used the threaded side only, instead of having them fold over.

The right side isn't so nice. The radiator cap relief tube position hits my tank, and so I can't mount the tank on properly and even if I push the rad forward to get it to fit it'll still put pressure on the hose and I'm sure it'll cut through. Also the bottom coolant pipe is about 3mm smaller than stock, so my stock coolant hose doesn't fit snugly - I've clamped it down but I'm pretty sure I'm going to need to get a new hose kit that matches this diameter. I've attached pictures so you see what I'm talking about here.

I've contacted the eBay seller, and I hope they help. It turns out I'm an idiot and didn't buy from GPI racing directly, but some other Chinese reseller who probably makes a couple bucks per-radiator they sell. I'm posting here both in the hopes that someone knows of an easy fix (that doesn't involve shipping it back to China) and also as a bit of a warning that sometimes these things aren't as easy as they might look.

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Edited by thewozza

I got the Mishimoto ones from ebay and had similar issues with the install of the cooling fan to the tabs...and the fan hitting the gas tank...and the horn...and the mounting bolts digging into the coolant tubes...and the oversized overflow barb... and the temp sending units hitting the gas tank.

But I don't recall having any issues with the lower radiator hose other than it being a pain to install.

The overflow barb was threaded into the fill neck so I removed it, cut it shorter and reduced it's diameter to fit the stock hose in a lathe. Maybe you can find a replacement barb that fits better.

They do state they have 30% more cooling capacity so you should expect them to be larger than stock though.

The overflow barb was threaded into the fill neck so I removed it, cut it shorter and reduced it's diameter to fit the stock hose in a lathe. Maybe you can find a replacement barb that fits better.

Hey that's a good idea, the overflow barb on mine is threaded too. It is larger diameter than the stock one too. My father in law has a metal lathe, I might be able to do something with that. I was also thinking that I might be able to bend it out of the way.

As far as the hose fitment, you can purchase stepped hoses

Hey thanks I was wondering about that. I think I'll need a 3/4" to 7/8".

And hey my local parts shop says they sell stepped down hoses, so I'll hopefully get this part sorted out today.

Edited by thewozza

Okay I have given up on these GPI aluminium radiators. I bought a couple used steel (stock) rads from eBay and I'm just going to run with those, they work great and install with absolutely no drama.

I'm going to put these aluminium rads up for sale as it is too late for me to return them to the eBay seller but I'd like to ruin any chances of me selling them by saying..............don't buy these radiators.

My list of problems:

  • lower rad hose was the wrong diameter and I had to buy a step-down hose from an autoparts store - this cost about $8
  • coolant relief spur was hitting the fuel tank when installed, and I'm sure the metal of the tank would eventually damage either the rubber or the spur itself - paid a machinist to relocate the spur to a sane place and weld shut the old hole, this cost $40
  • the spur itself was the wrong diameter (1 mm too big) so I had the machinist cut this down to the right size
  • the temperature sensors (fan control and the light control) wouldn't seal properly and just leaked and leaked no matter what I did

Seriously it was a bad time and I really tried to make these work. My experience putting the used stock units on? I bolted them on, threaded in the temp sensors and it worked. DONE.

I learned a valuable lesson from this, and hopefully you can learn from me. BTW I've got two aluminium rads for the DR-Z400 for sale - any takers?

Okay I have given up on these GPI aluminium radiators. I bought a couple used steel (stock) rads from eBay and I'm just going to run with those, they work great and install with absolutely no drama.

I'm going to put these aluminium rads up for sale as it is too late for me to return them to the eBay seller but I'd like to ruin any chances of me selling them by saying..............don't buy these radiators.

My list of problems:

  • lower rad hose was the wrong diameter and I had to buy a step-down hose from an autoparts store - this cost about $8
  • coolant relief spur was hitting the fuel tank when installed, and I'm sure the metal of the tank would eventually damage either the rubber or the spur itself - paid a machinist to relocate the spur to a sane place and weld shut the old hole, this cost $40
  • the spur itself was the wrong diameter (1 mm too big) so I had the machinist cut this down to the right size
  • the temperature sensors (fan control and the light control) wouldn't seal properly and just leaked and leaked no matter what I did

Seriously it was a bad time and I really tried to make these work. My experience putting the used stock units on? I bolted them on, threaded in the temp sensors and it worked. DONE.

I learned a valuable lesson from this, and hopefully you can learn from me. BTW I've got two aluminium rads for the DR-Z400 for sale - any takers?

Learned a valuable lesson too on Chinese petcocks......NEVER buy Chinese junk again! Your 2nd to last sentence says it all, bolted them on........DONE.

I bought a set of the chinese rads, the left side was resting on the exhaust, I had to 'massage' the bottom of the rad and elongate the mounting holes to get it up off the header. Otherwise they seem to be OK and are holding up alright, one side got a stick striaght through it but did not leak.

Yeah .. I bought a pair a while ago , I had to modify them to make them fit , no leaks though .

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