jpe's Bumble bee - The collected mods

[jpe70]

These things generally goes against all my instincts, but they can literaly save the day when there's no proper engine case protectors available. I'm talking about crash bungs, crash protectors or whatever you wanna call them. Usually chunky black plastic thing protruding from the frame... Hence I didn't really want to pull the trigger on the one's I found on eBay. Not planning on falling over, but you never know who will run into your bike when it's on the race stands. Last ditch effort I revisited some places I used to buy from back in the day and found these. Still protruding offensively, but not as horrid as the regular black cylinder of shame.

Gain: Already tried crashing on track with things like this at some speed. I could finish the day and ride 180 km's home instead of trying to keep oil inside engine.
Pain: Adds weight to bike and looks less than good.

LSL crash protectors from german dealer Louis (http://www.louis.de). LSL also still has rear sets for the 'Rex... This is the old style, they have a racing series for more money but this is still ages better than anything from R&G or eBay.





Yes, they will bend slightly in a high speed crash. But there is a spacer inside the frame tube so from previous experience should still be removable and I always have assorted bolts and tools along for track days...

[jpe70]

So, a late party post then. Project as such is on hold, Corona and what not, like a general lack of funds. I did however try to get a track day in before our now cancelled Brno-trip, and that worked less than brilliant. 3:rd session and I roll into pit early only to discover oil on not only left side of engine and my boot but also rear tire. Hang on, was that a slide I felt a lap ago? Nice...

First thought was I'd shot the seal to outgoing axle so ordered a new seal. Closer inspection in the garage revealed it was more likely an o-ring sealing a lid just in front of the axle instead. I had no idea it even existed and never heard of anyone changing it. But it was very flat on the outside so replaced it, must have given up the final ghost during the winter after many, many years of service and me flogging the bike past redline on the track. Hopefully that was it, if not I have a spare seal for the axle...

The bigger rear sprocket gave some better drive, but also returned me to the land of non-slip engine braking having to deal to some extent with an unstable rear end. Not as violent as a RSV Mille with non-working slip or even a stock TRX, but still.

Also first track day with TDMR's and TCIP4. Rode it with the ignition curve I got from Rune giving pretty much advance especially in low and middle. Not really impressed with the times I made, but the bike pulls decently now. Not much hint at all of bogging down on low revs/big throttle and pulls evenly up to 9-ish. Still seeing 1000 vanish on the long straight but the Suzuki 750's and bigger twins still remain in sight with a good exit. Didn't have time to experiment with curves due to oil...

Only advance on the project as such is replacing the handle bar rubbers with a set of Renthal grey mediums instead of the old nondescript one's.

Except riding, next step will probably involve Pieter at HPS Motoren, and unless he sells me more than I ask for there should be new fork internals and finishing the race prep on the shopping list once engine is sorted.

[Tarwetijger]

Was it the neutral sensor that was leaking oil?

What are you getting from Pieter HPS?

[jpe70]

Was it the neutral sensor that was leaking oil?

What are you getting from Pieter HPS?

No, there's a round cover in front of the axle (at the end of balance shaft?) that is only pushed in place with an o-ring and held with the larger plate that sits on the engine side. Didn't know it was there...

He quoted me prize for 880 kit, and seemed reasonable compared to just changing rings and honing barrels so plan is to go down that route after this season. Might even get an extra set of barrels for boring so I don't have to tear down the bike. No money for top end yet, so probably just change seals myself instead of going all out with bigger valves.

[Tarwetijger]

I don't know either then. And that bothers me.

[jpe70]

I don't know either then. And that bothers me.

Number 35 in this picture:

[Tarwetijger]

At first I thought you tricked me because I couldn’t find a 35.
Okay thanks for clearing that up.

[jpe70]

Instrument cluster

Koso DB-03R replacing stock clocks.

Finally, something's going on. Replacing stock instruments, this was on the list from the very beginning but not been a prio wanting to ride the bike instead. Beeing 2020 that's not happening very much, and when days are booked weather puts a pin in the wheel so to speak. So had to do SOMETHING.

Sorted throu cables and identified the one's I needed today and hooked the Koso DB-03 up temporarily to see if I managed to find the right ones or if it was going to blow in my face.
So far so good apparently.

Going to use the speedo, tacho, shift light, water temp and neutral light functions. Being a simple very analog track bike there's not much more sensors available or functions needed. Also 500 grams lighter than stock so theoretical weight just dropped below 180 kg. Need to check this on a scale any day.

Cables
Instrument need a constant +12V (red): Tap into red before ignition lock, there's a two-cable connector same place as the others under the tank.
Instrument ground (black): Several available from back of stock clocks. Pick one, marked "B" and attach.
Instrument power on (brown): Turns on instrument with ignition. Same as striped red to stock, there are two available from either tacho or temp. Use either one.
Instrument tacho (brown with connector): Connect to cable not red or black from back of stock tacho. Settings in Koso needs to be adapted. If you have Ignitech, adjusting in unit can help.
Instrument neutral (white): Just connect to light blue to stock neutral light.
Instrument temp (2-wire connector): Not sorted yet, but probably easiest just to replace the stock sensor in cooling system and use Koso connectors.
Flash lights, high beam etc: Just tap in to colored cable to corresponding stock lamp. Like yellow for High beam.

Youtube: https://youtu.be/hJ5q8T5Txrc

[jpe70]

[jpe70]

[jpe70]

So this was crap for track use. Get an RX-02 instead. DB-03 only usable for normal road use where time is slower.

[Tarwetijger]

So this was crap for track use. Get an RX-02 instead. DB-03 only usable for normal road use where time is slower.

You mean the dash? What's wrong with it?

[jpe70]

So this was crap for track use. Get an RX-02 instead. DB-03 only usable for normal road use where time is slower.

You mean the dash? What's wrong with it?

Nothing really wrong I suppose, just some issues. LED display is not the fastest so updates are kinda not always keeping up, did a test ride on the street and had no issues with it. Numbers on the rev counter are way too small to be easily spotted by a glance on track. Not a chance. Small for road use too, but matters less and there's usually more time for looking at it. I use 5 magnets to get higher frequency on speedo, but it still lags on track. Even on the TRX. Also seems there's a significant measurement error since I've checked circumference twice and meter is still not displaying correct speeds.

Gear shift light works, it's the only thing I actually can and do use on the track. It's set yellow for 8000 rpm and red for 8500 rpm, very small difference on those two in color so I shift when yellow comes on. Clearly visible in my face actually. If I shift late on red it sometimes keep blinking when clutch slips a little or rpm doesn't fall quick enough. Good thing I know the engine enough so I know not to shift again right away.

[jpe70]

Plans to remember and finding solutions for:

880-kit from HPS. Who will make the boring?
Ported head from Rune?
Change back to lighter stock swing arm.
- Get a axle sleeve for stock axle/R6 wheel made. Integrated drive side spacer. Contact? Measurements?
- Solve brake placement, either move torque arm fitting to top on swingarm or replace caliper/hanger with R1 + custom. Contact for welding?
- Alignment
- Get new dog bones to keep present height/attitude

Estimated weight saving 1,2 kg.

[cobbadiggabuddyblooo]

From memory the sprocket side rear spacer will give about 1-2mm clearance from the centre raised section of the sprocket carrier but you need to remove the sprocket attachment stubs and machine down 6mm raised section flush to get your sprocket alignment.
Then the world is your oyster to do as you choose on the brake side.