You can fit the Hebo 1L fuel tank on the headstock to a Vertigo with a few mods. You will probably need to re-locate the map switch and LED to somewhere else to fit the tank. Block the Vertigo fuel cap breather and make a new tank top breather bush from a short 12mm M8 hex head bolt, turned flat on top, centre drill then drill out to 4.20mm and thread M5 through the bolt centre. Get a GG or Ossa gearbox elbow and thread the end of this M5 and screw into the M8 "bush" with PTFE tape. There is a handy spot to drill and thread the top of the Vertigo fuel tank to take the M8 bush, we have a drawing somewhere to show this but you should be able to find a good spot. Run a decent petrol proof breather hose from the new vent to the Hebo tank outlet. The Hebo tank has a breather itself. When you are not using the Hebo tank, fit a ball check valve to the breather hose end to allow air to enter the tank. A very good friend worked this out initially. Bye, Peter B.
Hi Cribbs, for an air cooled 2T motor around 250cc, you would be looking for a piston bore clearance of around 1.5 thou, measured about 3/4 of the way up the bore near the bottom of the inlet and exhaust skirt. Most of the wear will occur in this area. This is just a rule of thumb guide. Bye, Peter B.
The Marzocchi USD forks are straight forward to strip down. Drain the old oil from each leg, loosen, but don't remove the M8 allen screw at the bottom of each leg. Remove both fork top caps and take out the spring. Remove both stanchions from the yokes, then the loosened bottom M8 screws, remove the circlips from on top of the fork seals then gently pull out the stanchion from the slider, sort of a slide hammer action to remove the bush and seal, take a note of the washer below the seal, this has to be in the right place when re-assembling. I got my seals when in Spain, but if you measure the ID, OD and seal height, you could probably find a Jap bike seal that fits. Bye, Peter B.
The Betor forks would work well with 5w oil, 200ml. Why 2 seals? There is probably some other problem like the stanchion jamming in the slider, perhaps the slider bush is too tight. The forks need stripping down to find the problem, try without the springs and without oil to see if the stanchions have full travel without jamming then look for the problem from there, it is not the oil. 5w is very light for Betors. Bye, Peter B.
Hola papapitufo, creo que fue muy amable de su parte el tomarse el tiempo para mostrar como se desmonta el eje primario Ossa, gracias. Lo siento si mi espanol gramatica es un poco malo. En ingles....The pinion at the end of the shaft is a very tight interference fit, and pretty good for about 3-4 disassemblies. With a bit of heat, you can use a standard Toldeo type bearing puller, I don't have anything as hefty (fuerte) as the puller you are using. We made a few modifications to improve the oiling around the gearbox, particularly to prevent the kickstart idler gear sleeve bush (casquillo de pinion intermedio) from premature wear. We drilled an extra oil feed hole through the inner gearbox plate, directly into the bearing. I experimented with different bearing materials, there was not a lot of options, for this bush, and ended up making a Delrin sleeve to replace the teflon lined bush. When the standard bush wears, it allows the secondary shaft to have a lot of axial play, which was accentuated when in second gear (the gear farthest away from the bush). This play was the cause of the whining gear noise when in second gear, as the bush wore out. If I can find a spare gearbox inner plate with the mod, I can post a photo of this mod, if interested. Saludos, Peter B.
It's possible that you were riding through a stream and water was sucked into the gearbox and clutch, hence the emulsified oil. I'd drain the oil and run a flush through it then try it out with fresh oil. Bye, Peter B.
Hi Ric, the posted drawing is of the later ball race type inner plate. This bearing does not receive any oil from the gearbox, it is a 2RS, sealed type (which I don't particularly think is the best), the inner plate has the oil feed holes blanked off.
Hi tsiklonaught, If you were to remove the oil seal to fit it the correct way, then yes, it will very likely be damaged, a new one is needed, viton. There is no oil pouring in from the feed holes, it is gravity fed from the gearbox, with the very small movement of oil through the bearing taking place by capillary action and the tiny amount of height difference between the in and out feed holes.
Here is a photo of my 2013 Ossa inner plate, that I removed to replace with a ball race conversion plate. It has the original oil seal in place. This is different to tsiklonaught's photo which I reckon is in the wrong way round and is very likely the cause of the gearbox oil entering the crankcase. Bye, Peter B.
Hi Ric, I disagree, there is no oil pressure, from the gearbox to the needle roller it is a gravity fed system, oil is tapped off between two tapping points through the crankcase to the bearing. Always, the spring of an oil seal faces the pressure side of a housing, in this case the pressure side is the crankcase. But, I can't tell from the photo if the side we can see is the spring side or not, it does not appear correct. I'll have a look at a spare Ossa seal and let you know. Bye, Peter B.
Just looking at the photo of the inner plate with oil seal, it's hard to be sure but I wonder if the oil seal was in the wrong way around, you should be able to see oil seal spring from this view, the spring always faces the pressure side, in this case the crankcase inner. With the replacement seal, this should be in viton due to the temperature limitations of other usual seal materials. Bye, PeterB.
Well, almost like that. As above, the PHBL26 utilises a fuel passageway and tapered screw to adjust pilot metering, located close to the reed block end. There is a similar looking carb from DellOrto called a PHBH26 which utilises an air passageway with screw adjustment, located close to the "bellmouth" end, usually a starting point for this one is with the screw fully in (clockwise), start with it being 1 turn out. I don't like this carb as much as the PHBL, it had a 2 stage pilot jet that used to always block up, and riding at different altitudes used to noticeably upset the carburation, more so than on the PHBL. Bye, Peter B.
Here are a couple of photos of the inner plate puller. Originally made for a Scorpa (Yamaha motor) flywheel puller, then modified for the Ossa using the inner 3 holes. The BCD, not accurately measured, is 42.0mm, check your stator hole placement. M5 bolt length = 70mm. Hard to see the third inner hole on the photo. (Two sets of 3 holes) Plate is 6mm. Hope this helps. You should be able to get someone to make up one of these. With the centre screw puller, make sure it does not damage the M10 thread at the end of the crank, I use a nut in between. Bye, Peter B.
You mentioned thick transmission oil that get's stuck on gears. We always used ATF Dexron III on these (and many others) bikes, which is certainly not thick transmission oil. Bye, Peter B.
The 2013 motors have a tighter tolerance between the inner plate and crank case and need to be extracted reasonably squarely. To remove the inner plate, remove the 3 stator bolts and hang the stator out of the way, then all of the plate bolts too. You need 3 long M5 allen bolts and a steel plate with a centre bolt, and 3 holes that match the stator bolt circle diameter (BCD) Use this set up to carefully extract the plate. I'll have a look for my extractor set up and see if I can get a photo of it on here. Some measurements too. Bye, Peter B.
I have worked on a couple of Ossa motors that smoked a lot, both had the following problem. On your motor on the crankshaft LHS, the needle roller main bearing runs on a thin steel sleeve which is a shrink fit on the 25 diameter crankshaft. The sleeve was under stress and ended up with a hairline crack, hard to see, that allowed gearbox oil to be drawn into the crank case. The sleeves are not available if yours is cracked, but you might be lucky and perhaps the oil seal has failed on the RHS of the crankshaft. If there is a hair crack on the sleeve, you can always fit the later model LHS inner plate with ball race, that runs on the 25 diameter crankshaft, so the sleeve needs to be extracted - easy if it is split. If the RHS seal has failed, which would be uncommon, then you have no option but to replace the main bearing and seal. Yes, it is a very lengthy job, and needs some setting up to put back together, but it is possible. Bye, Peter B.
You can always check the oil type, mineral oil has a definite oily feel, slippery. DOT 4 has more of a watery much less slippery feel. It would be unusual for someone to change the master cylinder kit to mineral and then the slave cylinder seals too. Bye, Peter B.
Hi Ricki, the Ice or Camo 300 with a low compression insert works really well. It takes the edge off the low end response and makes for a more relaxing ride up the becks. This size motor feels slower to respond than the Vertical 250. I haven't tried a Vertical 300 with a low comp insert, but imagine it would perform similar. Changing the inserts does not take very long. The 300 would be my choice from the 2 engine sizes. Bye, Peter B.
Hello sveson, the Spanish factories tend to use a fully synthetic 75W oil in the clutch/gearbox. The "W" stands for winter. Various companies can supply this oil, I am not sure what is available in Sweden, but some of the more familiar ones are GRO, Rock oil and Castrol. I have used ATF for well over 25 years in all sorts of bikes without any problem, always ATF rated to Dexron III. All of the Jotagas here run with ATF. Is it possible that you have had water in the gearbox? Although not a common wear point on these bikes, the water pump shaft/seal may have worn. Bye, Peter B.
Thats good information woody, you've had Bultaco's for a while then. The keyway ideally needs a repair job though probably not what you want to do right now. After fitting/locking in a new key, you could try using a Nord Lock washer under the crank nut, if you can find one with the right dimensions. I've used these with great success on other bikes, it is like 2 interlocking washers that lock in two directions. These guys have them down your way: https://www.hi-tensilebolt.com.au/product-category/washers/nord-lock-washers/ Bye, Peter B
I have 2 Sherpa's, both have an aluminium basket. At this stage, I'd check the flywheel if the crankshaft nut is tight. I had a similar sounding problem on my bike, that was the result of wear on the RHS parallel crankshaft, fixed temporarily with a special loctite, I think it was silver Loctite, whatever it was it could accept a clearence of up to 20 thou or so. Even though the crank nut was tight, the flywheel could still rotate on the shaft and sounded like your bike. 7 thou is a lot but that sort of clearance would make a ring a ding ding noise, not a heavy clump. Check the flywheel. You may be able to hold the magneto flywheel and then try to see if you can rock the RHS flywheel. Odly enough, your bike hardly makes any ringing noises. Could also be the primary chain, they never lasted too long before needing replacement. Bye, Peter B.
Can you supply the piston bore clearence 3/4 of the stroke length up, on the inlet and exhaust side. The noise does not sound so much like piston slap, but more like the right side flywheel is loose on it's parallel shaft, or the primary chain is shot. It doesn't sound like a big end failure either. Bye, Peter B.
Were those UK tank/seat units made by Hommerlite? I remember them being light blue and silver and prone to dents when you dropped your bike. Rustynuts, your bike looks really nice, I hope you get it all sorted out soon. Bye, Peter B.
Hebo number board fuel tank
in Vertigo
Posted
You can fit the Hebo 1L fuel tank on the headstock to a Vertigo with a few mods. You will probably need to re-locate the map switch and LED to somewhere else to fit the tank. Block the Vertigo fuel cap breather and make a new tank top breather bush from a short 12mm M8 hex head bolt, turned flat on top, centre drill then drill out to 4.20mm and thread M5 through the bolt centre. Get a GG or Ossa gearbox elbow and thread the end of this M5 and screw into the M8 "bush" with PTFE tape. There is a handy spot to drill and thread the top of the Vertigo fuel tank to take the M8 bush, we have a drawing somewhere to show this but you should be able to find a good spot. Run a decent petrol proof breather hose from the new vent to the Hebo tank outlet. The Hebo tank has a breather itself. When you are not using the Hebo tank, fit a ball check valve to the breather hose end to allow air to enter the tank. A very good friend worked this out initially. Bye, Peter B.