I had a 325 Beamish that used to do this pretty regular. I got ride of the bike before it killed me. I used to be able to stop it by putting a gloved hand over the end of the exhaust and pushing very hard.
Both makes are good choices, but.... steer clear of the 270 rev 3, probably a bit fiery considering your classic background, (unless you're going at 6ft rock steps) add the 200 rev 3 to your list instead , a great underrated little bike.
In 15 years of mudplugging in the Cotswolds and 3 yam scorpa's I've never had **** in the air box, . Even if muck gets between the mudguard and airbox the rectangular clamp/spring clip arrangement with jitsie filter is fiddly but when installed correctly works well. Be aware the rectangular plastic clamp only seals properly one way round. The jitsie filter is best, is it new ? they can deteriorate when old. Keep us posted .
Good choice on the new bike. No its not normal to lose coolant from the overflow, could be the previous owner overfilled the rad and the excess is blowing out when the bike warms up, or , and most likely,check the thermostat is bringing the fan on, if its not the bike will overheat and again blow the coolant out. Personally I use silkolene procool.
One thing I have noticed, is that the electrical wiring seems to be really rough, there was exposed wires where the insulation has come away, and I've covered this back up with electrical tape, and some wiring is exposed where the connection blocks are. Like I say though, it runs fine once started started, so I'm assuming the electrics are the problem, but it's the only thing I can think that's causing it.
That's a big clue, and maybe why the previous owner got rid.....by no means a common problem but I have known a few sy's that have had a broken wire in the harness giving a "completely dead" or "sometimes it will, sometimes it won't" situation, maybe the previous owner had a go at finding it if the harness has been hacked about ? You seem to have thoroughly covered all other bases. These venerable Yam motors are normally bulletproof, hence their popularity,so look at the scorpa part of the bike rather than the Yamaha motor. Keep us posted.
I have an '09 ex Birkett team bike. I concur with the mods previously mentioned, I would add, to my knowledge, the cranks were trued and welded to stop flywheel scissoring (not that it was a problem on yams anyway?) , mine has an Ohlins shock,(not sure that was a birkett mod) I know some owners who have strengthened the top shock mounting point as the bolt hole can elongate with time/wear. HTH.
The Birkett mod was to replace the studs and nuts with cap head bolts , that way once the bolts are removed the head just slides off without needing to lift the head over the studs which you cant without the head hitting the frame. A mod worth doing once you got the head off. HTH.
i'd suggest the new rings you've used are a tad to thick. The mid box should slide on lovely with a smear of grease without the use of any encouraging impliments. On a side note, the ally mid box is easily punctured/damaged where it touches the sharp corner of the raised boss on the crankcase where the engine numbers are stamped, Dressing the sharp corner with a file or dremel is a wise move if it hasn't already been done by a previous owner. HTH.
As an ex rugby prop I've always struggled in this regard with trials boots, I can just do up the Gaerne's I have at the moment on the loosest strap setting. I had diadora's before which had ample room in the calf but both pairs the soles fell off despite several attempts at repair. When trying on new boots I found I had to go 2 or 3 sizes bigger in the foot to get them to fit in the calf except the gaerne's. Good luck !!
The yam engine scorpa's remain a popular choice for novice/clubman. The bulletproof motor gives lovely
soft controllable power.
A long production run means engine spares are plentiful(not that you'll need them). Plastics can be pricey so don't ride like a loon and break them in the first place. Birketts will be your first call for
everything.
The sy250 remained virtually unchanged throughout its 9 yr production, graphics/colours getting the yearly makeover. The '08 bikes and '09(if you can find one) benefit from the better marrzochi forks rather than the earlier paolli, and also have a better designed bash plate.
The only issue to note is the centre exhaust box can rub on the motor, easily rectified (if it hasn't
already) by grinding/filing the sharp corner off of the raised engine number boss.
I've had 3 sy's and love 'em. My '09's deffo a keeper.
You could do no worse than invest in the book -BSA unit single engine manual by "Rupert Ratio". Literally worth its weight in gold. Tells all about parts interchangability down the years Good luck with the build.
Yes, 2009 was the last year of production of scorpa's with the bulletproof yam motor. Birkett only imported 20 odd '09 bikes before scorpa ceased production, so you may wait a while for an '09 to come along.
Best off looking out for an '08, plenty off 'em about, only difference from '09 being the usual styling excercise decal changes.
Good call keeping hold of your old bike for spares, the yam engined scorpa's ('01 to '09) remained pretty much unchanged throughout the entire production run, so spares interchangabilty is good.
I have an '09, but she's a keeper I'm afraid.
Wish you well in your search, secondhand sy's do seem to hold there value more than the other makes as they're a popular choice with novice/clubman.
Ref rear mudguard. I've always drilled through the brass bolt holes in the airbox ,you can then attach the rear mudguard using thin cable ties rather than bolts. That way, if you do flip the bike over backwards, you just snap the cable ties rather than the mudguard. Cable ties being a LOT cheaper than rear mudguards.
Spare cable ties are easily stashed somewhere on the bike should you need to do a repair mid trial.
A smear of silicone sealer where the ties penetrate the airbox prevents the ingress of water.
Maxing our revs during ride!
in Bultaco
Posted
I had a 325 Beamish that used to do this pretty regular. I got ride of the bike before it killed me. I used to be able to stop it by putting a gloved hand over the end of the exhaust and pushing very hard.