When building a bike, or anything for that matter, have a plan. ‘While you’re in there’ becomes a very slippery slope. ‘Future-proofing’ always ends up costing ten times more than you thought it would. As the shakedown track day approaches, I was going over some last-minute checks on the Ducati. I noticed a little wet spot on my brand new front tire. Tracing the little dribble line it appears to be coming from the coolant reservoir.
The 916-998 radiator does not have a pressure cap, instead, there’s a hose that runs to a plastic bottle with a pressure cap tucked away in the frame just behind the headstock. They’re very prone to cracking at the seams with repeated heat cycling and leaking. Stock used replacements are $30-50 but are almost guaranteed to fail without warning at some point. Luckily the aftermarket has stepped up and offered solutions. There’s a nice aluminum tig welded reservoir for approximately $225.
Then I came to learn this reservoir like the stock ones, prohibits the use of the Ducati Corse style larger airboxes that are common upgrades for these machines. I hadn’t planned on getting a fancy $1000 airbox, but you never know. No sense in ruling out that possibility now. EVR, who makes the Corse airbox, also makes carbon pressurized reservoir replacements at approximately the same cost.
So I searched for a better solution. Ditch the stupid capless radiator altogether. When Ducati transitioned to the 999 in 2003, they used a radiator with pressurizer cap. Presumably, this was done to remove the old-style coolant reservoir to fit bigger airboxes to make more horsepower. Ducati 999 radiators are $50-$100 on eBay. The inlet and outlets are almost identical.
6 comments
Great article!
Thanks Matt! More coming soon!
Love it! Man… you have a 675 track bike too?! I’ve been eye balling the Street Triple to replace my 600RR for the street bike, but I haven’t convinced my wife to let me keep the 600RR too for a track bike. I just know I can’t sell the 600RR before picking up a new bike or there will be 0 bikes in the garage and it’ll stay that way, ha!
In my previous job,, I learned the hard way about o-ring material and compatibility with different types of fluids. Even different types of oils. Who knew that one type of oil would react differently than another type of oil?
I found this site for material compatibility with all sorts of fluids:
https://www.marcorubber.com/o-ring-chemical-compatibility-chart.htm
Most generic o-rings are EPDM. Which is probably what you have. I’d recommend stepping up to at least NBR (nitrile). FKM (Viton) is the baller stuff which is typically easy to get.
I can’t recommend the street triple enough. It’s arguably more fun even on the track than a fully faired machine depending on the track. The first generation ‘R’ models are the absolute jam, and they’ve made basically the same bike for so long that they’re dirty cheap on the used market.
The fuel pump o-ring was a real bummer. I ended up sourcing Viton replacements from McMasterCarr. They’re much less susceptible to ballooning up after seeing fuel. Newer Ducati’s use Viton, but they’re something like $50ea. Sourcing them 3rd party saves something like 70% of the cost.
Im nearly two years late, but I am wondering if you still have the bike and if so, how it is running. Ive got a 998 and your radiator solution is intriguing. Im so tired of how hot my 998 runs. It really is my ONLY complaint of an otherwise awesome machine. Any updated info especially concerning the radiator would be appreciated. thanks.
Hi Will, I most certainly still have the bike. I’m not sure this one will ever leave. I still ride and race it regularly. I have however changed the radiator setup again. So as you see here some compromises were made to use a 999 radiator. Ultimately I had some failing very old radiator hoses and came across a screaming deal on a set for a 998 style radiator.
So despite the work I did to get the 999 rad to fit, I reinstalled the cleaned 998 radiator, Samco hoses and pressurizer tank. Now of course I’m left with a RH air intake that I’ve modified to make room for a radiator cap that I no longer use, so I ultimately need to replace that with another unmodified unit.
All that being said the radiators are functionally the same, same basic size, capacity etc. I don’t see a huge benefit either way. I’d say the stock setup is a bit easier because of fitment.
In your case the heat complaint just leads to more questions. Is the bike overheating or are you just not enjoying a 200*F Vtwin right under your balls at stop lights?