BSA A65 Ôit’s a bit like an old Du­cati Mon­ster’

Motorcycle News (UK) - - This Week -

“It’s based on a sim­i­lar bike built by a com­pany in Ja­pan called Ber­ry­bads,” says owner and en­gi­neer John Jones. “But I’ve built the whole thing round the Amal GP carbs. The rear frame tubes and side pan­els are scal­loped in to make room, and the long in­let tracts are there for the look. So from be­hind you can see the carbs suck­ing air in, and the si­lencers blow­ing ex­haust gas out.”

The orig­i­nal A65 con­tained the seeds of the idea, but the fac­tory never got round to mak­ing it into a styling fea­ture. They also never got round to solv­ing the A65’s ap­palling vi­bra­tion is­sues. John’s done that with a Dave Nour­ish 90-de­gree crank­shaft, at the same time adding a large dol­lop of grunt with an 830cc con­ver­sion that needed a set of late-model (1970 on­wards) crankcases to take the strain. “I got the en­gine built by Rayner Trau­pel in Ger­many,” says John. “He was the only guy I could find at the time who could build a BSA with a 90-de­gree crank.” These con­ver­sions are far from straight­for­ward; they need cus­tom cams, pistons and ig­ni­tions too. The big-bore alu­minium bar­rels are a Trau­pel spe­cial­ity; the Brummy orig­i­nals are cast iron.

The rest of the bike is crawl­ing with amaz­ing de­tail. John wanted the clean lines of a speedo in­cor­po­rated into the head­light, which he found in a Nor­ton Nav­i­ga­tor 250. The Lu­cas switches have to be re­versed so they don’t catch on the ca­bles and kill the ig­ni­tion. Clipons are Daytona Omegas with vernier an­gle ad­just­ment. The swingarm is a com­plete one-off. The rear LED light is al­most in­vis­i­ble un­til it switches on. The alu­minium seat was made on an English wheel by a sports car body­work ex­pert. Rearset footrests on a BSA are usu­ally in­com­pat­i­ble with a kick­start, but weeks of care­ful de­sign have solved that peren­nial bug­bear. More cun­ning still is the horn: it’s the rub­ber bung in the mid­dle of the tank. On the orig­i­nal bike the bung cov­ers an anti-vi­bra­tion mount.

The bike feels light and lively to ride. The old-school carbs make it gur­gle a bit un­til it hits a sweet spot, at which point it cat­a­pults you for­wards, rather like a sin­gle switch­ing to a twin. Hook up a gear and it does it again, with the thrust ef­fect ar­riv­ing in fourth (top) at 70-80mph. It’s a bit like an old Du­cati Mon­ster, but with bet­ter steer­ing and weight distri­bu­tion. Cor­ner­ing on the chunky Avons is com­pletely neu­tral.

The orig­i­nal A65s vi­brated like road drills and were built with their wheels three eighths of an inch out of line to try and re­duce weav­ing caused by the lop­sided en­gine. If only BSA had done it like this.

What’s the ap­peal of a Brit cafe racer?

Jim Hodges “I went through a mad pe­riod in my 30s. I had a ZZ-R1100 and a 916, which were ab­so­lutely fan­tas­tic. But ev­ery time I went out I was nearly killing my­self – com­ing back shak­ing.” John Jones “I’ve done the R1 and Du­cati track­day thing, and I don’t want to do it again. I scared my­self. The beauty of these bikes is you can have fun at sen­si­ble speeds.”

How did you learn to build bikes like this?

Jim Hodges “I’d al­ways had Bri­tish bikes too, and I used to be re­ally anal about orig­i­nal­ity. I had a to­tally orig­i­nal Hur­ri­cane, and put it back

Clever and con­sid­er­ate de­sign solved the age-old kick­start/rearset prob­lem Build cen­tres around Amal GP carbs the show Daytona clip-ons steal

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