Aprilia RS250 - Money Pit

[Hosewa]

Hi All.

A few details on my RS250 project, some of you may recognise from the Aprilia Forum, but I'll pop a summary in here and some pics once I get a bit Flikr account sorted.

I ended up buying a pretty physically challenged Aprilia RS250 way back in October 2005 and then the rot truly set in! Three years later and it's still not running, let alone finished. I've spent nearly double what I had originally thought when I started (with another few grand still to go) but it's been awesome! The end result will be a bit of overkill in lots of places but I got to the point where I am really not wanting to compromise given how far I've came and what I really wanted to build all those years ago. I've not kept a record of time actually spent on the bike, as there have been lots of occasions where months have gone by (or for this year, a year) where there has not been much going on. If it ends up being 4 years till it is done, my excuse will be that it was really only 2 if you count actual time on the bike!

The rebuild has been stalled by rapidly dwindling funds in the project account, two garage break-ins, two house moves, two workshop moves and four holidays in the last two years. I've done what I could myself and farmed out what needed to be done by others. I've spent way to much on some things that I suppose were not strictly necessary (replacement forks, custom triple clamps and brake lines and electrical connectors) and the packaging of the components has evolved a bit during the build as well but it's been a lot of fun. Here's a bit of a brief on the spec so far and (hopefully) some of the finished product which I am hoping I can get down to 120kg with all fluids except fuel:

Chassis:
Frame/Swingarm - 98 Aprilia RS250 stripped and painted matt black
Rear Subframe - Stock modified for equipment mounting (oil tank, shock can, battery)
Rear Suspension - Technoflex rear shock adjustable for ride height, pre-load, rebound and high/low speed compression
Front Suspension - 2005 GSX-R 600 forks and custom triple clamps, stock RS250 steering stem and offset.
Brakes - Braking wave disks front and rear, front radial callipers from 2005 GSX-R 600 with HEL brake lines and 19x18 brembo master cylinder (folding lever), stock rear calliper and master cylinder, HRC fluid reservoir

Engine:
Stock Aprilia RS 250 with high flow air filter, re-jetted to suit stainless steel Jim Lomas exhausts (polished by hand in front of the telly for a few weeks) with a fresh top end
Cooling - Original thermostat and radiator piping removed, ZX-6R radiator fitted with custom cooling link pipe and silicone hose kit
Maybe some engine mods one day, but for now I need to get used to the handling mods and get some laps in before I start chasing (and spending more money!) on more power.

Miscellaneous:

Custom wiring loom with quick-disconnect connectors (work in progress)
Electrics relocated to front of fairing, Koso race tachometer, compact battery
Modified oil tank under seat (a cut-down and plastic welded stock item)
Dunlop Alpha-10's in stock sizes
Woodcraft foot pegs (with stock levers) and clip-ons
Venhill (UK) high performance teflon lined actuator cables for powervalve, clutch and throttle
Domino quick action throttle
Lightech folding clutch lever
Carbon hugger and front guard

A big post, but it's the first one in this index so might as well have a red hot go at it.

Pics to follow soon, but here is a teaser.



Cheers

[hybrid]

Nice one mate, it definitely looks the goods!

[JonW]

Ohh yes! now were talkin! more pics please

[hybrid]

Just realised we probably should have an Aprilia forum too considering they are probably the most popular Strokers these days.

Have created a forum and moved this thread here.

[davidj]

Looks great! Are you staying with the 98' bodywork? Or up dating with the newer more "wedge" looking kit. (that seems to be popular now) Anyway keep up the good work and lets see some more pics.

Dave

[Hosewa]

Thanks for opening up an Aprilia Thread.

They probably benefit from being the last dealer backed up 2T you could get so there are still a lot around that are pretty stock.

Dave.
I'm keeping the stock shape bodywork, I thought about going for a Tyga style kit (I've seen the RGV kit fitted to some RS's) but I think the shape is part of what makes these unique looking and the GP bikes were still similar up to this year.

Cheers

[Hosewa]

A few things that I modified. I figure I can top up the oil tank after each session when I top up fuel (I never run with a full tank anyway) so looked at options for a smaller oil tank. In the end I hacked up the stock one and tried my hand at plastic welding. It is a bit rough and ready and not the most attractive thing (I will paint it eventually) but all sealed up it turned out OK. You'll see where it now fits under the seat in a later post.

[Hosewa]

The relocation and packaging of a lot of the ancillaries (battery, ECU, CDI, shock can) came to a large degree from the shock can not fitting in the original location. There is not a lot of clearance for it as standard, wedged between the airbox, the top shock mount and the original battery location. The new shock was slightly bigger and it was looking pretty ugly as it was going to be touching everything and that did not seem like a good idea given how much the bike vibrates and it was also going to be pretty difficult to reach the adjusters.

I moved the oil tank as in it's standard location it's a bit venerable to crash damage and looks a bit clutted.

So, I decided to ditch the stock undertray and move all the things around. I also took the opportunity to try to lighten up the sub-frame by basically chopping bits off it! Seeing as it is never going to have to cope with a pillion, and as I tend to carry a lot of weight on my legs on the track, I figured I could afford to loose a bit of the over the top strengthening braces etc. I did briefly consider making a new one, but maybe one day in the distant future.

I wanted to be able to access everything pretty easily especially the oil tank, without too much bodywork having to come off and to try to bring the weight as close to the centre of the bike as possible. I have a nifty little pip pin to fasten the seat and tank to the sub-frame, no need to fool around with the allen key bolt now, nice and quick. Whatever form the replacement undertray takes (most likely just a sheet of fibreglass a few plies thick dzus fastened to the tail unit) I can make some cut outs to get to the shock adjusters from the rear.

These pics and those in the next post show how all this got developed and fitted up and also the HRC rear brake reservoir and the rear brake line routing.

[Hosewa]

Seat pip pin.

[Hosewa]

Assembled before painting.

[Hosewa]

Fully assembled after painting.

[Hosewa]

The new front end.

Why, well partly cosmetic, partly performance. Having a newer front end updates the overall look of the bike a bit and I suspect I might get slightly better performance out of the brakes. More importantly though, these forks have a very good reputation of being of good quality out of the box on the stock GSX-R's. I will need to get them re-built once the bike is done to suit the bike weight, but I think it is pretty safe to assume that they will be significantly better than the old stock items and despite being larger in diameter, they are actually lighter. There were lots of ways to do the conversion and I have seen others do something similar. Some use complete front ends other a mixture of bits and this is sort of the route I went down, though if I knew what the end cost would be I'd probably would have gone for something simpler.

I wanted to keep the standard wheels and also the standard geometry. I figure if at some point someone is selling a set of nice light RS250 race wheels then it's going to be nice and easy instead of having to find a mixed set or get two pairs to get one pair (if you follow me). As far as the geometry goes, if you use a complete front end from anther bike you can introduce changes, mostly because of different fork off-set. Now I'm no suspension or chassis guru, so maybe it makes no difference, but I figured I would play it safe and try to keep it stock.

This meant I had only two options for the triple clamps, get the lower once machined out to take the new forks (there are 1mm larger at the lower clamp point but the same as the RS at the top) or have new ones made. It would have been way cheaper to go for option 1, but I was dead keen on the idea of some nice custom items, which was eventually the path I went down.

The advantage of this in the end was everything fits perfectly and lines up really well. Simply machining the claps out to suit the forks would probably have required a new axle at the least and there was no certainty that I would be able to get the callipers and disks to line up properly. The clamps are not much lighter than the stock items, but much nicer looking and a lot stiffer. It also meant I could re-use the much lighter GSX-R axle (which oddly enough was the right diameter for the RS wheel) with a bit of modification by the guy who did the clamps.

Was it worth it? Given I wanted something special I suppose yes, but if I knew then what I know now (especially the cost!) I would probably just modified the stock clamps. Still, I have something unique and I am very happy with the product.

Old on the left, new on the right.

[Hosewa]

First fit-up of the new bits.

[Hosewa]

The fitment of the new radiator proved to be a bit easier than I had first thought, in some ways at least.

As you can see from the pics the clearance is a bit of an issue, but I can still get the full travel out of the front forks without hitting the rad so that has to be a good thing. I trimmed most of the mounting lugs of the new rad but kept the top two outside ones. A few new holes in the stock top rad mount and that was all sorted, so now I am in process of making up some braces for the bottom (I have had to remove the stock bottom braces from the engine sub-frame) and that's the mounting sorted.

The hard part is the plumbing and getting a few of the unused outlets sealed up. Re-using the stock pipes from the outlet of the water pump to the barrels is the go, and there was in the hose kit I bought an existing hose to go from the rad outlet to the inlet of the water pump no problems. The other end of the equation was a little more complicated. Basically I had a new 'T' shape alloy pipe made to route the head outlets to the rad inlet, the routing of this solid pipe was a bit of a challenge as the route from the top head is pretty cluttered. I also need to get a boss welded onto the radiator to take the temp sender and a few drain plugs as well.

Only problem now is the lower part of the rad is fouling on the bodywork. No dramas with the top section and the rad is no wider than the stock item, but the bellypan narrows off really sharply, it would be nice if the transition was a bit more gradual and then I'd be set. I have a few options, but one means the bodywork will sit lower than normal and may affect ground clearance so I think in the end I'm going to have to re-profile the bellypan to clear the rad.

I've done some composite work so I'm happy to give it a shot and see what happens I guess.

[Hosewa]

The T pipe