Classic Motorcycle Mechanics

PROJECTRIC­KUKI

Scoop pokes a sharpened stick at his long term project and waits for it to bite him on theº

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Steve Cooper re- starts this troublesom­e special.

If perchance you were wondering what might be happening with Project Rickuki then you’re not the only one! ve occasional­ly rediscover­ed the rolling chassis as ve gone looking for stuff around the garage and made a mental note that really need to get back on it again. However, as seem to be blessed with the retention span of a sh these days often uickly then forgot about it. The fact is my good mate Dave, who volunteere­d to make the reed-valve carriers, has (over the course of several months) moved workshop, waited forever for a sparky to wire his machines up, and asked someone else to do some of the machining who then disappeare­d on holiday for ages (no, that wasn' t me before you ask!). Specials such as the Rickuki seem to entice problems like a feral cats attracts eas. The good news now is that machining is done and can be paired up with the aftermarke­t Mikunis: well almost. The left carb ts ne but the right oat bowl annoyingly hits the very top of the oil pump. Sometimes specials can indeed be very special! Hopefully we have a plan but it' s yet to be executed: once again it' s suck it and see' time. Elsewhere things are actually looking rather positive. Rob Pemberton of SPA Motorcycle­s, the guy who convinced me actually wanted this project in the rst place, has pulled the motor apart to see if it' s as good as was claimed. When acq uired was told the motor was fully sorted and while had no reason to doubt the claim it' s good to be reassured. The crank is sound and although the rods have been used before there' s no

damage or signiae cant wear. t' s a big old lump designed to be robust and reliable but uite why it needs to weight close on fteen kilos is anyone' s guess. That said this relatively large mass probably accounts for the low revving, loping, easy going nature of that uniq ue motor. Even if the bike was rst drawn up in the mid-60s there' s internal evidence of some advanced thinking here which may very well have come from MZ via Ernst Degner. nside the crankcases are packer ribs designed to reduce the volume beneath the pistons and thereby increase primary compressio­n thus speeding up fuel/air transfer to the combustion chamber. While it might not look like a lot of metal in the words of a well-known supermarke­t' s advertº every little helps! Thankfully whoever built the motor added plenty of oil so the likes of the little-end eyes are in robust health, ditto the main and big end bearings. One job that does need attention is replacemen­t of some faux-engine studs that are actually DI store studding. Now know why there were some apparently spare Suzuki studs in that box of spares: note to self, never throw jack away until the job is done. Anyone who knows much about Suzuki T500s will tell you they' re potentiall­y notorious for taking out fourth and fth gears. Even after Suzuki modiae ed the castings to blank off a semi-blind casting that robbed the box of precious lubricant and added an extra 200ccs of gear oil, high mileage examples can make the most appalling mechanical whining sounds before the top two cogs go AWOL. Thankfully my gearbox has been pronounced tickety-boo, so no vast expenses or hunting down rare partsº well not just yet anyway. generally try not to get too enmeshed (sic) with gear boxes but Rob P reckons the T500' s is actually uite an unusual design. Apparently the selection dogs are not on the backs of the gears as is the case normally. This means all ve gears are constantly being driven on the input shaft. Now whether or not this is a good or bad thing is totally beyond my ageing brain but evidently can take some reassuranc­e that it' s not an unheard of set up. Seemingly amaha used an extremely similar system on their mile eating, six-speed, JR13 00 so we can all sleep easy knowing that.

The cylinder heads will get a check over for atness at the gasket face and will also be carefully volumed to ensure we' re okay to run on modern unleaded. They' ve already been heavily reworked post installati­on of the water jacket. The spark plug holes have been relocated centrally and also upgraded to take long reach plugs that will, in theory at least, better dissipate heat. Knowing Rob P' s love of two-strokes and his passion for getting the best out of each and every one the barrels have had a serious talking to. Vast amounts of swarf, some steel but mostly alloy, give witness to the black art of two-stroke porting. The aim is to liberate some extra ponies yet not make the bike overly peaky. look on seriously impressed as Rob gradually disappears under an ever-growing pile of metal debris. Apparently both my inlet and exhaust ports have now been proae led, matched, harmonised and upgraded. This will aid inlet lling and exhaust scavenging along with improving gas/air transfer from the crankcases to the combustion chamberº and all in the name of ow dynamics. So far, in this episode of Rickuki building ve not spent any money yet! ve told myself that the straight cut primary gears bought some years ago no longer counts so nancially m doing well. The idea behind using this style of primary drive that eschews the more convention­al helical teeth arrangemen­t is that straight gear absorbs less power due to reduced friction. They may be noisier but that' s not really an issue now as my hearing is shot to hell anyway. However, the old auditory organs perk up when Guru Rob mentions might be interested in a close ratio gearbox. He reckons that to make the most out of the reworked motor our combined interests would be best served by opting for a Nova Transmissi­on T500 CR Kit Type B. This is not a cheap option but it does take out the chasms between most of the shift changes. Most crucially it will allow the bike to maximise on both torq ue and power. n case you were interested according to Nova: the B kit comprises a new input shaft with rst and second gears machined on the shaft and a press on third input gear; also supplied are rst and second output gears. The Nova output gears must be built onto the customer' s standard output shaft with standard Suzuki dog rings. The standard Suzuki input gears must be pressed onto the new Nova input shaft.º So now you know and yes my wallet has been signiae cantly lightened. More news as it breaks and as soon as ve got over the shock!

Thanks this month to; Nova Transmissi­ons 01403 711312

 ??  ??
 ??  ?? Right-hand reed block and carb.
Right-hand reed block and carb.
 ??  ?? Bits that make up the reed valve.
Bits that make up the reed valve.
 ??  ??
 ??  ?? Checking the selection dogs.
Checking the selection dogs.
 ??  ?? Can you see the packer ribs?
Can you see the packer ribs?
 ??  ?? Crank set-up.
Crank set-up.
 ??  ?? Little-end eye.
Little-end eye.
 ??  ?? Checking engine studs.
Checking engine studs.
 ??  ?? The blind casting.
The blind casting.
 ??  ?? Lower engine case/gears sorted.
Lower engine case/gears sorted.
 ??  ?? A Rickuki cylinder head.
A Rickuki cylinder head.
 ??  ?? Primary gears.
Primary gears.
 ??  ?? Porting in progress.
Porting in progress.
 ??  ?? Swarf in the hole!
Swarf in the hole!

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