F5 Dave’s F5 bike gets a birthday

**F5 Dave** · 15th April 2014, 12:36

Well that’s the plan. Bike has been looking a little shabby of late. It was tickled up shortly after transplanting the RG engine into the RS, but that was like 2006. I’d given the bodywork to a mate & said “Surprise me”. That’s how I’d ended up with Black with a sunburst of blue flame. He used to paint Bruce Anstey’s TZs & they got black & stickered & often crazy wheel coloured.

Anyways, after my ignominious defeat at the last GP I decided it needed a bit of a birthday. The seat unit fibreglass was a bit torn & flappy since Katie threw it up the hill at Kaitoke, so that was the first thing to get fixed.

It has held up well & was on the previous RG, heck I bought it off Regan (GPR lad) back, er probably late 90s/2000 earliest and it was a lightweight number.

It was a bit mullered by now so I ground away at the back & matted & epoxy resined it. It’s a bit heavier than traditional poly resin but its far less smelly, petrol resistant, and far more importantly, I still had some left.

Ohh doesn’t it look pretty?

- No actually it looks dreadful, but it’s a basis for giving a sand & slamming on some paint, which the same mate from above dropped around for free. He can’t paint it these days so I’ve chosen Enamel which is petrol durable & not super toxic + a muppet can put it on which leaves me mostly qualified.

I had hoped to get it sorted at Easter, but some other little projects on the bike have popped up so we’ll see.

The question is: Will I have it ready for Kaitoke? (27^th Ap)

**F5 Dave** · 16th April 2014, 09:24

but wait, what's this?

**F5 Dave** · 16th April 2014, 09:48

Well I've taken the plunge to fit a Derbi GPR50 engine. I don't think this strictly makes me a team GPR member, but I think they have to pay me royalties now, which will help as I'm on a shoestring these days.

I've done about 6 engine transplants over the years so I'm getting quite experienced. I'd like to hope that meant I was getting good at it. But sadly it doesn't & I'm still making a bit of a pigs ear of it. Having one fixed point to reference off is bloody useful. Sadly I'd cut the rear ones off & rewelded them to fit the RG engine. DaveDip used the std rear ones & made a cradle for the front.

So I had to make a cradle for the front & then weld on some new mounts. I am hoping to be able to fit the RG engine back in if need be, but it turns out that I will need to carve a section off the back of the engine & weld it shut to do so. I have to pay for my all welding. I can do steel, but only pretty badly.

One should always make a jig to hold the mounts still while they are welded. I used the engine to line up where the mounts would be and filed some interface points & ran a bolt through to keep them in line. I didn't want the engine next to the welding as it gets jolly hot. Anyway this was a mistake as one side hard up against the frame/ ground mount stayed pretty much ok but the other which needed some filling to join the space to the frame rotated back and around. Bugger. so a weekend of elongating the holes so it all lines up again & fill the back of the holes.

Next time I'd spend the effort to make a jig to replicate the engine or just use the engine, but when you take the engine out which you have to to do more than just tack it can still move so a jig is better, just harder to make & you need to have raw material.

I've actually had this engine for about 9 years & slowly done it up. I would have done things differently now so I'm not totally happy with the spec but we'll see how it goes. My RG engine is last over & the barrel is oval so something needed to be done & I have this engine.

So to get it to Kaitoke weekend after Easter I need to refit the holes. Last night I checked the compression ratio as I'd forgotten whether I'd done it & there were no notes. I also fitted the stator as last stage of a few days tinkering. Then I need to wire up the ignition, & fit things like gear linkages, rad pipes etc. Biggest concern is the pipe which in a dry run hit the sump plug. This could be a show stopper for a short term get to the track fix.

**Pumba** · 16th April 2014, 10:08

Hmmm, while reading this am I starting to get a deja vu feeling with this thread.

**koba** · 16th April 2014, 19:22

Choice!
I may end up copying both of your steeds...

**chrisc** · 16th April 2014, 21:04

I spent about 3 hours the other night researching these engines, barrels, etc. I'm interested...

Here's a photo from the 2014 GP at Tokoroa as an example of said bike "looking a little shabby of late." Although I'd argue it looks like a lot of fun!

_MG_3525 by sonscc, on Flickr

Rest of the album is here: https://www.flickr.com/photos/sonscc...7642282552865/

**F5 Dave** · 17th April 2014, 09:46

Thanks man great photo. My leathers match the bike, . . .and the budget.[edit] look at the miss matching gloves

Weldy guy fixed up the holes better than I expected & fitted the bolt back in saving me hours of filing.

Easter will give me some time to work on it. Well it better, It'll only leave me a week till the next race. Have to make sure pipe & everything else fits, then need to shag around fitting the flywheel in the correct place.

**F5 Dave** · 18th April 2014, 16:23

Engine fits. Needs a tickle to make it fit nicely. Pipe is close. Won't hit plug which is nice, but one hits sw arm. A bit of a bend seems to almost sort it. Think I can make it work. Just need some time. Think the loom and ign timing will be the key things.

**F5 Dave** · 22nd April 2014, 17:03

Ok well engine in bike. Radiator hoses sorted. Chain & sprocket sorted for position. Gear linkage remade to suit. Pipe & mount fitted. I had to bevel the back of the muffler to avoid hitting the swing-arm but that was an easy change that means it still fits if I refit the RG engine.

Still to do:
Clutch cable
Ignitec loom
Find stator timing position
Start, program a flat curve to start with & tune jets, best fit for a safe run

And probably a few things I haven’t thought of yet. It'll be tight considering how long it took to find the stator position on the 100 with an undefined stator position, that can burn up a bit of time, remeasuring, restarting the bike. I have found that the timing goes off the trailing edge of the rotor which will help considerably.

What I'm not happy about is with the taper adapter it doesn't bite onto the taper with enough agression so that you can do the nut up without it turning. Once I find the key position the woodruff will hold it still to enable it to be done up & deform to grab, but I may try match with some valve grinding paste to see if I can get that push on/grab lest adjustment will be a wind-up.

**kel** · 22nd April 2014, 20:38

Looking good!
When you have a few spare dollars I can hook you up with a guy that can knock you up a custom cylinder and head good for 18hp, what's more it has a whopping 3.5k power spread.
OR
you could buy one of those off the shelf, bolt it up Bidalot cylinder kits for just a couple of hundred

**F5 Dave** · 23rd April 2014, 09:17

Nice troll.

This Octopus is the Loom almost finished based on my 100 one but with only 1/2 the tricky stuff connected. The loop at the side is all the wires I won't be using but will retain for later development if I feel like it.

Just has the pulsar coil feed, stator to charging cct, rec reg which I'll be pinching off the 100 for now as I have a 5 wire scooter reg but have to confirm which wires are what & its extra wire I think is lighting, the coil output, the wire to the on switch & the power feed back to everything else, then I've added the PJ connector for future, TPS wires, the shift light which I'll hook up now, & quick shifter, but I doubt I'll have made a bracket in time. Get it going first huh?

**F5 Dave** · 24th April 2014, 14:24

Eeet Leeives

traditional push it to top of driveway, let out clutch and it fires straight away. clutch needs to free itself a bit, but its been sitting a decade. water seems to be circulating. Charging system working. timing where I marked it. Setting up the ignitech was a whole heap easier the 2nd time.

Sounds a bit flat & rich at the bottom, but I'll do a dyno trip & sort where we are at. . .erm maybe tonight?

I'm not saying its ready to race, but

Eet Liveeess