hencam

The time has come for some new shocks for my Bultaco, it is a 198A sherpa, so shock length 340mm. however for a mere mortal clubman rider what do I go for, budget is £250 max. however I am confused.com There are Betors, which I have fitted currently, budget range circlips to adjust, work fine, just thought I would snaz the old girl up a bit. Betors expert range? Sammy Miller Betors again clubman and expert? NJB's not had alot of success with these, however not had a pair for about 5 years? New range of Betors available from Dave Renham at in-motion? Falcons? so open to suggestions or peoples personal preferences

Not at all, I thought it was you, we were having a laugh at sections 4 and 10, i was on a blue Sherpa 198, you gave me some advice a few weeks back on an Ariel I was buying. Thanks again and hopefully I will recognise you next time. I did buy the Ariel in the end and am currently trying to get it trial ready in a basic form. if i like it then i will look for a more up to date frame and possibly short stroke it .

Jon, were you riding an AJS today?

could not agree a more with both topics of the thread, an excellent day despite the weather, thanks to all observers who stood out there for us to have fun. and yes sad news about Bill and Mike, the classic scene will not be the same without them.

Dear All, a bit more info on registering your classic trials bike I got fed up in the end with phoning the dvla and the fact i could not progress the pages on the online form, they were helpful but could only send me hard copies of the NOVA 1 in the end. Then I read all the stories about people getting forms returned for the slightest imperfection and honest and genuine mistakes costing them money, i also found out that the DVLA will not accept a dating letter from Dave at in-motion and would have to ask the VMCC who charge £27. I did have the MOT, passed with flying colours!!. Woody then replied to another posting suggesting I try the people below http://www.dvlaadvice.co.uk/. so I did, David Williams I think was the chaps name, you pay £95 and he sends you 100% crystal clear instructions, so simple i phoned him twice to make sure I had not misread! The whole process took me about 10 days from receiving the paperwork, i had the NOVA 1 back within a day!!! then hey presto reg number and V5 arrived after a week and 3 days later the tax details. I honestly cannot recommend these guys enough. is it expensive? well you have to make your own judgement, £65 for the luxury, but no more phone calls or hassle and he supplies you a dating cert, NOVA 1 and V55. No more worrying that telling the truth is not what they want to read. I bought my Bulto 8 years ago from an autojumble in Bristol, paid cash £300, had a receipt at the time but lost that years ago. all these question make the NOVA 1 tricky to complete if you genuinely have no evidence or detail to support your form. hope this helps H-cam

Hi All, finally managed to scrape together the pennies for a basic Ariel, very different from the Bultacos, i normally ride. my sincerest thanks so far to John Bartram and JonV8 for the advice and guidance so far. The bike is an early Bartram frame, with a 1958 motor, interspan converted mag and Burman Box GB47, standard 500cc motor. as I am still recovering from the purchase and funds are tight (I could have bought 4 bultacos for i paid for one Ariel) I am trying to do the bare minimum to make it rideable in a trial. currently it is unrideable, carb worn out, and gearing way to high, bald back tyre, sadly it also running on Castrol R at present, not the best apart from the smell. So the Carb is a well worn 626, i don't think i will get away with just the slide, if i buy a new carb do i go for the 626, and does it matter where i get it from, for example a wassell type or Hitchcocks Amal, what would be a good starting point for jets please? now the gearing is 19T on the engine 42T on the Norton Clutch, 19T on the gearbox and 48 on the rear wheel. It has already been suggested i go to a 12 or 13T on the engine, possibly down to a 16T on the GBox and a 54 or 56T on the back wheel, all this is fine, not sure i will get as small as 16T on the Gbox as the chain is rubbing over the top of the swinging arm now, although i guess a larger back sprocket would help. Any suggestions on gearing please? would a pair of Michelin X11 be ok as a starting point? or are there preferences for a larger pre-unit bike that i am not aware of? any help and suggestions gratefully received.

Thankyou Woody for a once again logical, down to earth answer, that is a very nice looking C15 you have there, is it a tubless rim?. My decision is based out of practicality, to be honest i have no desire to, neither do i have the ability to ride in any championship. particularly as i would end up riding against a lot of people who can afford to disguise their mods by fitting Jap or European inners in there british fork bottoms etc, i like polished alloy, but can't afford alloy billet cub hubs, and this i would find frustrating if i was put in a different class because i cannot afford to disguise it.. that said i have no issues riding in a specials class and rules are rules. When i first ventured back to classic trials in the Somerset area i remember watching the 'Hand' brothers ride their immaculately prepared Tiger Cubs that are equally beautifully engineered. instead of riding in the pre-65 or what ever it is called now they road twinshock 'A' and still invariably won the trial.

Many years of collecting and riding Bultacos means my father and I have number of relined/rebuilt Sherpa wheels, the later type single sided not full width. we are currently building a couple of Pre-65 C15 trials bikes that we hope to compete on in the Pre-65, Pre-67, Pre-70 what ever the class is that the all the other C15's on the day are entered into. the engines are C15G, so 1966ish, they will hopefully have B25 Alloy barrels fitted. One will be in a Drayton frame, one will be in a modified WD B40 frame, both will have forks with spindle mounted underneath, not leading axle. We normally ride in the south and south west ACU and AMCA, if we fitted the Sherpa wheels, (i can skim the ribs off if required so they would look like a Rickman), this is for ease of having all bikes with the same wheels and only having to keep one type of shoes, Sprockets, ease of swapping, affordability, and the fact they are a nice looking wheel, would we be able to use these wheels without offending anybody, breaking any rules that others have not already broken. They are accepted in Pre-65 Motocross along with Grimeca, Maico and all other manner of hubs, i have also seen many other non pre-65, non British hubs in the pre-65 class at the trials we normally ride in. help suggestions gratefully received, i am not trying to start a debate , neither am i holding a giant wooden spoon !!

All, i am hoping to fit a B25 Barrel onto C15 crankcases, also using the C15 head. many have already done this mod, my question is how do you get the oil back to the crankcases as the drain holes in the B25 barrel only one is the correct side as the C15 has them diagonal. can you drill down the side of the barrel and put a pipe in?? could you mill a track around the gasket face on top of the barrel from the where the drain hole from the c15 head meets the barrel? i have only seen one one and he had a very late B25 barrel and there was enough 'meat' to drill down the side? my B25 barrels are earlier and don't have enough room, hence my question about pipe?? as always any suggestions gratefully received?

Hi all, i am hoping to return to riding a C15 or 2! one in modified WD frame and one in a Drayton if i can raise the pennies! anyway i am currently building the motors at present, my question is what size chain do people use. 428 or 520, i always used 520 when riding 10 to 15 years ago. one bike will have cub hubs, the other probably Bultaco. Both engines are C15G they will be running B40 WD gearboxes. i have no sprockets or chain bought yet, so it makes no difference £££ wise. just wondered what everyone uses and why if they have a preference. all suggestions gratefully received.

Hi Luke, this is my suggestion based on opinion and limited experience of the unit BSA single. personally i would measure the bore to piston clearance by sliding the biggest feeler you can get between the piston and bore in the area the piston travels. measuring using a digital caliper, vernier caliper or bore micrometer is ok, however the feeler gauge method is more reliable and in most cases is what an engine reconditioner would work from. similarly to when having your barrel bored if you are prepared to run it in you can ask for it to be bored tighter clearance, perhaps 0.002" or 0.003" thou as opposed to 5 thou if you need to get on and race the bike. a tight bore will give better performance and overall will last longer as the piston cannot float about or slap. so back to the original question. my suggestion would be measure piston to bore clearance, check what the service limit is, i can't remember for C15 about 0.009" i think if it is within this then a light hone/glaze bust will remove the polished surface and help new rings bed in. This will also tell you whether you need a re-bore or not, if its close to the limit save the grief and hassle and have it bored. if it is well with the piston clearance limit, in my opinion the best way to check which rings you need is to purchase both and try them in the bore, most supplier will accept the ones not needed back if you are prepared to pay the postage. Again there is a piston ring end gap service limit, so with your new rings either size, for this explanation start with the standard rings, place one in the barrel half way down the bore, take the piston, place it skirt down on the ring and turn it 180° back and forth to level the ring in the bore. then look down the bore and measure the ring end gap using feelers, again if it is close to the service limit, personally, i would forget it and try the +0.020" rings. do exactly the same with the piston, it is most likely these rings will either touch on the ends or have slight over lap. if this is the case you need to file the ring end back equally on each one until the ring end gap is the what it should be with a new piston rings and bore. use a fine file and have patience, it is worth it. keep trying until you have the desired ring end gap. if you only want to buy one size of rings I would go for the +0.020" in my experience of the unit BSA you will be lucky to get away with std. you may find some NOS 0.010" rings as these were once available in the good old days!! only one other thing, speaking from experience the ring thicknesses on modern pattern pistons, sometimes differ from the good old Hepolite type. so if you have an original piston try and find some NOS rings. if it is a modern type GPM etc then buying the rings should be easy. Hope this helps cheers H-Cam

Hi all, as usual this forum comes up trumps with advice and guidance, many thanks Woody and Totalshell. I will contact VMCC and find out what the score is now! A very Merry Christmas to all and a Happy and Healthy 2015. all the best Hencam

I am well aware this has been done to death and I have scoured the postings to date. situation is this: I purchased a Bultaco 198A about 9 years ago, it was purchased secondhand from a private individual, can't remember exactly but about £300 I think. to the best of my knowledge it has never been registered. I want to register it, so the MoT is booked, should pass, (it had a pre-mot check last week), I have been asked to put a reflector on it. I have ordered the V55/5 form from the DVLA Dating cert from in-motion has been recieved. insurance quotes saved awaiting use! my first question, do I need a NOVA1? I started to complete this but once i got to the section asking me about supplier details i am unable to fill it in. my memory does not go that far back, I can't remember sellers name or anything about him, i did get a receipt at the time but have lost it long aga . So if i need the NOVA1, how do i complete it?? 2nd question, the Engine and frame numbers do not match, frame is a RB198 0**** - A, engine is RM198 0****, so slightly earlier engine, 1979 and 1978 respectively. The original engine suffered serious damage to the crankcase when the gearbox mainshaft broke up, until about 3 years ago I had kept the original cases as they came with the bike, however I weighed them in thinking I would never need them as they were not repairable. I always understood DVLA were only interested in chassis numbers, is not having the original engine likely to be a problem, and if yes, any suggestions as to how I can overcome this please?

Hi Trum, i too would be interested in the RH brake arrangement, i am currently on a cable, its next to useless, new shoes (softer material) relined hub in steel, new cable all moves freely, brake is still C**P, no feel to it what so ever and if you really need it to work and stand on it the cable might as well be a piece of elastic. i have contemplated cross shafts etc but can't see a way to do it!

Glad you enjoyed it, most folk in the motorcycle world are pretty friendly, the trials circles particularly so. The culprits responsible for your excellent days fun, and indeed mine were Ian Guy, Mike Popperwell Kevin Eddols and their respective partners who all support and run the South Coast Scramble Club. Obviously not forgetting the landowner for access to a very nice piece of trials ground and observers and other unsung supporters. I hope you will join us again, there are a number of trials clubs in and around the area where the primary focus is fun, most aimed at classic bikes with a class/classes for beginners on more modern machinery! I am not sure where you are from or what bikes you have but Somerton Classic, Somerton District Mcc, Dorset Classic Scramble club, Wilts and Dorset Mcc all run some excellent events. The advantage with most is that the sections are challenging without being intimidating, offering a range of routes including a 50/50 route at some, and there is always someone on hand to help in whatever way required, be it physical dragging you out of the ditch or mud! or advice guidance on bike type, performance, problems and riding techniques etc. no idea who you are, I was on a 1978 Blue Bultaco Sherpa 250, hopefully we will see you again.

Just wanted to say a very big thankyou to all who were involved in today's trial at Cadnam/Canterton Southampton. I did manage to catch up with Ian, Mike and Kevin but there are always many others involved. Thanks to the landowner as well for the use of such a splendid venue. In my opinion and quite a few others who were riding round an excellent day, a well laid out trial with 'thought about' sections that had at least 2, sometimes 3 lines through them and which were certainly well suited to the Pre-65's, twinshockers and novices. some of the lads on modern monos were no doubt finding it a little easy. thanks also to Marjorie for manning and supporting the charity cake stall with some delicious homemade cake and very nice cup of tea, i hope you raised a good few quid!

Hi Woody, thanks for the rapid reply, yes using the Michelin tubeless, I have already seen the many posts on IRC, we had used them in the past and were always happy until we fell victim to the inconsistencies, when your spending £70 - £80 you can't take the chance. It had also not occurred to me that part of the problem may be that new tyres grip so much better than 20 years ago so therefore more torque is transmitted through the tyre exacerbating the problem. looks like i am not alone, so will get on and accept and make the best of it.

Evening all, My father and I run a number of Bultacos, 250s mostly, in club trials in the Wiltshire, Somerset and Devon area , I tend to ride a little more often than him and in a few larger events such as the Exmoor 2 day etc. I am just trying to build the picture here. Bikes are pretty standard, Bulto wheels and Akront rims 1.85" width. we have run IRCs and Michelins on the rear and generally prefer the Mich. we do not skimp on items that matter such as tyres, tubes and security bolts, we run two security bolts as is the norm, the problem is rear tyre creep. I have tried most makes available on the market, some billet types from well known sprocket manufacturers to those available from dealers in general. After any wet trial the tyre will have crept round to the point it needs pushing off the rim and pulling back round. I am 15 stone (most of that is riding gear honest ) and run between 3 and 4 psi. Dad is a little heavier and runs 4 - 5 psi, is this problem the norm, or am i missing something, not doing them up tight enough etc. we have been riding for a few years and just don't recall ever having to do it so regularly. any help advice as always is gratefully received

Hi trum, not sure if i am using the correct format for replying to your post, I am sure the experts will correct me, apologies in advance for any wrong doing!. I have a large stock of Bultaco parts mostly used, as my father and I have been riding, repairing and restoring these excellent bikes to what our budgets will allow for the last 10 years or so, as anyone knows if you have a penchant for a particular bike the collection of parts just seems to grow. If you get stuck please message me I am sure to have a set or two lying around. kind regards hencam

Ok, so i think i am starting to understand????? if the stem is parallel to the stanchions it steepens the fork angle, i think sherpas are normally leaning in about 1.5° at top, i would have though putting the stem in parallel would have increased the rake and made the steering shallower. so if i machine up a new pair of billet yokes with a stem running parallel to the stanchions it will make the bike react slower because the trail is increased, i assumed it would steer quicker. or am i completely missing the point and when people talk about parallel yokes the are referring to the stanchions being in line almost with the stem if looked at from the side on view instead of sitting in front of the stem by 'X' distance. i don't really have a problem with my sherpa steering, i am not competent enough a rider to be able to worry, however as i like making nice parts for my bike, which is where the pleasure comes in if i can improve it, it would be nice?? can somebody please explain in an easy to understand way

can i enquire please as to what the "steering stem" mod is please, does it involve the 1.5°ish stem angle

there is a very good place in North Devon www.torridge-districtmcc.co.uk/ John Luckett has some excellent ground which i believe this club use. normally advertised in back of TMX. i am sure they advertise camping weekends and trials holidays

Hi Trailie, thanks for the info, have sent e-mail, does not look to hopeful though not on the books listed. I remain hopeful somebody may have a copy for sale in the UK.

I am hoping someone can help with finding or selling me a copy of a book.History de la Sherpa T the story i wanted it for a birthday present, the publishing company in Spain are out of stock and i missed the one for sale on ebay by a £1 in the last 5 seconds :( . it was destined for a birthday present. if someone has a copy and would want to sell it i am happy to pay a fair price for it, desperate is not the word!! i would really appreciate it and thanks in advance to anyone may be able to help. i was also after the Motorcycle trials techniques and training by Lane Leavitt and Len Weed twinshock , although this was not quite as important. all the best Hencam

hi, happy to be corrected by those in the know but i believe if you have the washer and a spring then you have the earlier type, the ball and spring type have the countersunk screw in the top. the washer and spring type flap valve arrangement were fitted to the earlier bikes. however i would guess the problem is the same though regardless of type, it is probably too much oil i hope this helps