robcbsa Posted December 10, 2015 Report Share Posted December 10, 2015 Hi Guys i'm after some info on Ariel short stroke motors I've got the start of a project ie a bottom end crank cases steel flywheels later rod also a 350 head which I've been told can be modified to fit a 500 short stroke barrel there are a number of people selling these are any more preferable for this mod as I think i'll have move the head bolt hole centers ? Quote Link to comment Share on other sites More sharing options...
bibbo Posted December 10, 2015 Report Share Posted December 10, 2015 I have seen a 350 head modified to fit, but as I understand it, it is A LOT of work. I know the remade 500 heads are expensive but it's worthwhile. As far as I know only Mick Dickenson does the barrels for short stroke. Maybe a few places sell them but they come from the same person I think. 2 Quote Link to comment Share on other sites More sharing options...
hencam Posted December 10, 2015 Report Share Posted December 10, 2015 Hi Guys i'm after some info on Ariel short stroke motors I've got the start of a project ie a bottom end crank cases steel flywheels later rod also a 350 head which I've been told can be modified to fit a 500 short stroke barrel there are a number of people selling these are any more preferable for this mod as I think i'll have move the head bolt hole centers ? Hi, I had similar plans, when I owned my Ariel, a number of people gave me considerable help. John Bartram from South Street, South Molton, Devon and a chap on here Jonv8 (Jon Cull) Bath area , Nick Smith also from Devon, George Greenland is also well worth talking to as he also had some considered and valuable input and in my opinion built one of the nicest short stroke Ariels I have seen. John Budgen does barrels and heads. Mick Ash makes gears for the Burman box. I would have liked to have completed the project but did not want to spend a disproportionate sum of money on an a bike already well above my capability. so I left mine long stroke. Quote Link to comment Share on other sites More sharing options...
hencam Posted December 10, 2015 Report Share Posted December 10, 2015 I've just picked up a 1985 59n model ty. It has a chrome frame and Swingarm, I've never seen one like it before and wondered if it was some sort of special or just done by someone who wanted something a bit different? The chap I bought it off thought it had been like it from new. I've bought it as a winter project and wanted to get it all powder coated and looking nice. Has anyone seen one like this? Cheers I owned a very nice TY in the southern centre, sold it and the next time i saw that it was chromed Quote Link to comment Share on other sites More sharing options...
collyolly Posted December 11, 2015 Report Share Posted December 11, 2015 Have you got 500 crankcases ? I think they have 5 stud mounting for the barrel and the 350 has 4 stud although it is probably just a simple matter of drilling and tapping the missing fastener as the castings were possibly all the same. The head I think you want has an internal exhaust port rather than an external stub, these are now becoming rare and expensive. I have a short stroke bike and it 'rides light' compared to the long stroke original in fact feels very modern, well worth the effort if you can source all the parts. Quote Link to comment Share on other sites More sharing options...
robcbsa Posted December 14, 2015 Author Report Share Posted December 14, 2015 Thanks Gents the cost of new a head may just be the straw that broke the special builders bank balance Quote Link to comment Share on other sites More sharing options...
robcbsa Posted December 15, 2015 Author Report Share Posted December 15, 2015 Has anybody got contact details for Mick Dickenson i'd like to get a short stroke barrel Quote Link to comment Share on other sites More sharing options...
charlie prescott Posted December 15, 2015 Report Share Posted December 15, 2015 Hi Guy's. Rob Ring, Alan Whitton. Regards Charlie. Quote Link to comment Share on other sites More sharing options...
robcbsa Posted December 17, 2015 Author Report Share Posted December 17, 2015 Thanks Charlie. Quote Link to comment Share on other sites More sharing options...
trialsrfun Posted December 19, 2015 Report Share Posted December 19, 2015 I know little of the Ariel engine modifications mentioned, please explain which is the preffered mix of parts and what are the benefits gained. Quote Link to comment Share on other sites More sharing options...
jon v8 Posted December 20, 2015 Report Share Posted December 20, 2015 The idea of the short stroke is mainly that it picks up quicker,and equally important - shuts down quicker.The original longstroke motor is a lovely engine to use,but is a real handful in todays tighter sections.Its also an inch shorter in height and a bit lighter,all of which helps. The parts needed are a 350 crank and rod assembly,a short stroke barrel from Mick Dickenson. You then need an 86mm piston,usually an XT350 or XT500 Yamaha one.The standard 500 head is used,often with the inlet stub cut off and rewelded to get it inline with the bike,rather than sticking out the side. A Mk1 Concentric or Villiers S22 carb does the fuelling. For ignition some people hide a modified Electrex world unit on the end of the crank,the one made for C15's can be made to fit.Others use the Interspan electronic mag or the BTH electronic unit.Few seem to use an original Wader or BTH mag,or if they are there it is for show only... The only problem I can see,besides the overall expense is to make sure you don't create an engine that it too much to handle,compression plates and a healthy amount of ignition retard are the order of the day. 1 Quote Link to comment Share on other sites More sharing options...
charlie prescott Posted December 20, 2015 Report Share Posted December 20, 2015 (edited) Hi Guy's. Hi TRF. OK quick run through. First you need a NH 350 bottom end. with everything in New or good order. You need to drill and tap a fifth stud hole for the Mick Dickinson short alloy barrel. You now need to try and find a HT VH cylinder head ,near impossible now, so you will have to buy a newly cast one. You then need to find a Yamaha XT 350 piston or one with the same measurements. A month of meticulous machining and assembly and you may have a Scottish winning motor. PS and a BT-H electronic magneto. and Villiers S22 carb. Regards Charlie. Sorry Jon you got there before me. edit because I was to late , always am. Edited December 20, 2015 by charlie prescott 1 Quote Link to comment Share on other sites More sharing options...
trialsrfun Posted December 20, 2015 Report Share Posted December 20, 2015 Thank you for your replies, do most or all of the winning bikes have this spec then? Quote Link to comment Share on other sites More sharing options...
laird387 Posted December 20, 2015 Report Share Posted December 20, 2015 The idea of the short stroke is mainly that it picks up quicker,and equally important - shuts down quicker.The original longstroke motor is a lovely engine to use,but is a real handful in todays tighter sections.Its also an inch shorter in height and a bit lighter,all of which helps. The parts needed are a 350 crank and rod assembly,a short stroke barrel from Mick Dickenson. You then need an 86mm piston,usually an XT350 or XT500 Yamaha one.The standard 500 head is used,often with the inlet stub cut off and rewelded to get it inline with the bike,rather than sticking out the side. A Mk1 Concentric or Villiers S22 carb does the fuelling. For ignition some people hide a modified Electrex world unit on the end of the crank,the one made for C15's can be made to fit.Others use the Interspan electronic mag or the BTH electronic unit.Few seem to use an original Wader or BTH mag,or if they are there it is for show only... The only problem I can see,besides the overall expense is to make sure you don't create an engine that it too much to handle,compression plates and a healthy amount of ignition retard are the order of the day. Hi Jon, That's why I learned how to restore magnetos - the modern electronic systems are very clever but lack that vital element of adequate advance and retard - and I say that as an electronic engineer. Deryk Quote Link to comment Share on other sites More sharing options...
robcbsa Posted December 20, 2015 Author Report Share Posted December 20, 2015 Hi Guys thanks for the info had a great chat with Alan Whitton & then Mick Ash both very helpful , My stumbling point is the head I just lost one to a fellow club member . I asked Mick about using a modified 350 head but from the problems he had it looks like a no go, My next plan is to talk to Alan again & see what size the bore of a Mick Dickenson barrel is pre machining & if will take a smaller liner with enough room a less modified 350 bolt patten without welding If it could take a 78mm id liner gives a 400cc engine with small ports & valves to keep gas speed up at low RPM a Honda CRF250 piston has been used by somebody to give me the best of both worlds . Your thoughts as always are most welcome gentlemen. Rgs Rob Quote Link to comment Share on other sites More sharing options...
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