Jason's 848


This project began with the lucky find of a crashed bike. We had originally planned to overhaul Jason's 748 race bike, but because this 848 presented us with a VERY inexpensive starting point, he decided to go ahead with a whole new project.

Project Goals -

1 - Check over the motor but keep it stock
2 - Tune the bike to make power but also to make it as easy to ride as possible
3 - Reduce weight wherever possible
4 - Upgrade the suspension to make it handle perfectly on the track

These four goals should produce a bike that is reliable, and easy to ride. Having only been racing for a year, this should help Jason go faster than simply building him a high performance motor.

Here's the bike as it arrived to us -


Once we checked out the bike to make sure it was a good and safe project candidate, we decided to strip off all the damaged street parts. The damage was spread over both sides but the main impact of the crash seemed to be on the right, and as is common with the 848 / 1098 an impact on a solid foot peg bent the frame tabs. They were only slightly bent, and we straightened them out, and made sure there were no cracks or other issues.


Next up was to fit the bodywork so it could be sent out for paint. But, before we could do that we needed to install the new exhaust mid pipe so we coulud check clearance etc. You want to have the bodywork perfectly fitted and drilled before it gets painted - trimming and modifying things afterwards is not the way to do things. The bike arrived with Arrow slipons, so we decided to keep them and select a new mid pipe. The QD pipe we chose goes from narrow header pipes to a very large mid section crossover then back down to the stock size to join the slipons - 52mm/60mm/54mm. This should help keep up the midrange torque without limiting top end power too much. It will also save a bit of weight over the stock piece.


Next, it was time for a light weight subframe from our Friends at Yoydyne. We'll loose that heavy plastic undertail too.


Now we are moving the 30mm Kyle Racing Triples and Ohlins forks from Jay's bike to Jason's.

Note the coolant overflow bottle!

Jay's fork seals were leaking a bit - we had just replaced a couple sets, so new seals are on order - we'll sort them out in a few days. In the meantime, this is what you need to watch for: Oil on the slider, and oil on the brake caliper mount.


Pulling Jay's forks, starting with the top triple.


Sad Jay, happy Jason:


The lower head bearings on Jays bike were bad - likely from moisture getting down into the steering stem - Jay notches the lower bearing race so we can pound it up off the stem.


Stock forks coming off Jason's bike


The Ohlins forks each weigh a full pound less than the stock Showa forks, but we wanted to see if what the complete assemblies weighed including the triples. They were the same down to an ounce or so. So any weight advantage of the Ohlins is offset by the additional weight of the stronger triples.


Cutting off the stock steering stops and touch up with a little Ducati Red.

Why we always wear safety goggles!


And, on go the new forks!

And, to pay respects to the closing of BCM, today Jay wears his old shop shirt, and remembers the good times up in NH!


And, after a small break, we are back at it, beginning with the rear suspension.

Here's the old stuff, and then the new stuff!


We've got a Dan Kyle modified TTX - setup for Dan's linkage, the linkage itself, which is designed for a more linear rate as we don't need to worry about typical street riding two up stuff, and a Ducati Corse ride height adjuster. This adjuster is going to be a bit on the long side when used with the rest of the components - Dan has a shorter one that allows adjustment all the way down to a stock ride height, so we'll probably be trying that one as well eventually. Jason liked a lot of ride height on the 748 so he wanted to try this corse one first.

Here it all is going in - the bearings in the linkage get a little lube and the seal from the stock one goes right in.

Lastly we put a little zip tie in there so we can see how much travel we are using up when we start to get it all set up.


Next we spent the day pulling everything off the bike that we don't need, and doing some general fixes and left side cover work.

First thing is these coolant connectors - their o rings don't sit proud enough and they leak. A little sealant takes care of it.


Left side coming off, and notice the lightweight flywheel - a nice thing to have as stock!


This tab lock washer isn't up to the task, so we replace it with a serrated belleville one, and then loctite and torque down the nut.


Next up is the shifter mechanism. These usually are a bit off as set from the factory. The pins should both align well with the tab, and produce an even wear pattern. When they are this far out it can miss the pin and jam. You can see there's only one wear line on the face - the other contact point is so far off it's hitting the edge of the tab instead of the face.


It should look like this (this junk piece is seriously worn, but shows where they should be hitting):


Here you can see how far off the pins are:


The alignment of the faces should be equal and spec at .375" You can see they don't quite fit. So, we adjust the spacing and are good to go!


Now that the left side cover stuff is done, we can take care of the stuff under the right side cover. We are going to install a Yoydyne slipper clutch and remove a little stuff we don't need.


Clutch is out, now out comes the water pump.


As with the rest of this bike - notice the attention to lightness that Ducati has given this thing from stock. So nice to see.

We are removing this sound deadening stuff and anti - chatter parts. Every bit of weight helps.

Inspecting the clutch plates. Looks good, so we'll re-use this stock clutch pack.


There is an anti-chatter ring with two rings that goes in the stack - you just can't start or end the stack with it. Regular one on the left - special one on the right.


Here's the Yoydyne piece, looking very fast already.


Ducati puts the last fiber plate in set off one notch from the rest of the basket. Presumably this is an anti - chatter thing as well. Yoydyne doesn't specify this, but we'll do it the Ducati way.


Loctite the nut and torque it down.


Springs and keepers go in, and you are all set!


We spared you the pictures of Jay scraping sealant off the mating surfaces with a razor, but here's the right cover with a nice new coating, and on it goes!


Bolts go back in - don't forget the long one goes at the 8 c'clock position.


Here we have a lightened and very pretty rear rotor. Still works well, despite there being so much less of it... weighs about half of what it did stock.


Jason wanted a shorter turn throttle, so here we have the Ducati Performance (Accossato) race throttle. It comes with cables, which we lubed and installed. Also the Brembo radial master from Jason's 748 goes on, and DP Sinstered pads in the calipers too. Note - we didn't like the over the top routing on the throttle cables and wound up running them under the bar like the WSBK team does.


And the now the moment we've all been waiting for... No more key!


We wanted to get a baseline Dyno with the stock ECU - not too bad around 122hp at the wheel. Don't worry - we'll get lots of dyno sheets up here soon! Note the borrowed tank... gave Jason some ideas about paint schemes...

Matthew finds 4 valves a bit dull.


But he does take a good picture! Here we are beginning to work with the Nemesis. The control you have with this system is amazing. We'll have more for you next time!

We finished tuning the 848 with 127hp, and quite a bit more mid range than the stock ecu gave us. We are going to run it on auto tune at the track to polish it up.


Next up is getting the final drive sorted. We mounted up the 16.5" Michelin Power One slicks only to find that there was very little clearance with the eccentric in it's stock position here.


To figure out what we could do with the eccentric, we needed to get the gearing sorted and cut and mount a new chain. Jay sights along to make sure that there isn't going to be any offset as we migrated this quick change over from the 748.

We rolled the eccentric back, but couldn't get the chain length to work out with our 40T sprocket.


We tried a 40T and laid out the chain and found that this sprocket size allowed us to roll the eccentric all the way back. Who needs a mag swing arm anyway! We cut the chain, riveted in the master link, and added a little loctite to the sprocket nuts.


Next up we double check the chain tension to make sure we haven't been over enthusiastic about the whole eccentric thing. Unbolting the ride height rod allows us to check the tension at the swingarm's maximum deflection to make sure the chain won't pull. A jack under the midpipe makes it easy to lower the middle of the bike. Passed the wiggle test on the chain!


Fork seal time! Top comes off and the process begins.


After cleaning everything the new seal can go in. We are leaving out the dust seal to reduce sticktion as this is a race bike.


Fork oil goes in.


Pumping the cartridge up and down to fill it with oil and eliminate any air bubbles that could make our oil level measurement miss. As these are 130mm travel forks we are going to start their setup at 120mm of fork oil.


And now the next leg. Jay guesses right on where the hole is!!


While we are at it, we check for clearance against radiators. Not bad, but we are going to cut the brackets off the bottom of the radiator to give us a bit more in case we need to drop the nose a bit.


Totally bottomed. Big tire!


The crank position sensor need a bit of sealant to prevent it from grounding - can be the cause of an intermittent stutter under power.


Nifty bracket to the end of the tail in place - with no under tray it would vibrate like crazy.


And finally, on goes the bodywork. Time to go racing!!!!!!

We'll keep you posted as it evolves over the season.

THANKS FOR READING!!