Ian T
Members-
Posts
29 -
Joined
-
Last visited
Contact Information
Recent Profile Visitors
The recent visitors block is disabled and is not being shown to other users. |
-
Ok thanks to you both, much appreciated. The length is the same as the M49 spec ones then. I have the remains of the spokes I cut off (in another thread on here I cursed myself for not keeping any samples, lesson learnt...) so I can measure the angles.
-
Hi lorenzo, thanks for the quick reply. Oddly this is for the front wheel - maybe the rear Pursang spokes on the larger size fit my full-width front hub too.
-
In my model 49 parts book beside the front wheel spokes it has written in pen, probably by my dad: "use 86-04-003/5" I think this might be because the rim he was using had a different ERD (effective rim diameter) to the standard one. Does anybody happen to know (or can look up) the spec for these part numbers. It should be spokes, and presumably there are two different angles for the inside and outside spokes. Thanks!
-
Spot on! Thanks so much. That'll be a big help! I may give Sid's wheels a call, see how competitive they are with Central Wheel.
-
For the older bikes I think zinc plated spokes look more 'period' anyway. I have a Greeves scrambler to rebuild and that will definitely not have stainless ones! Now that you mention it I remember that my parts book is shared with the M27. Could you do me a massive favour and measure the inside length of the longer spokes, and the total length of the middle ones in your picture? Before ordering new spokes I'm trying to get the lengths right, and not sure whether I can trust the parts book! As I cut all my spokes (stupidly!) I can't measure the lengths, but I can estimate the angles.
-
Problem with the M49 is that some of the spokes are supposed to have extra bends, so it's difficult to source them. Nice work on the plating, it's something I'd like to have a go at. My dad did have a zinc plating kit but unfortunately one of the chemicals leaked and ruined it all!
-
Who did the paint? Looks like a really good finish. I think I'm going to order spokes in the next day or two. I will use the lengths from the parts book and make a little jig to put the extra bends in. It's a bit of a gamble but not sure what else to do. The other thing that I'm not sure about is the angles for the heads of the spokes. I think the inner brake side ones may be a little more than 90 degrees, maybe 100 or 110. Neat idea actually. Did you bore both bushes in one go? I have some adjustable reamers that should do the job.
-
A couple of minor updates. First all that gearbox detent. After soaking in penetrating oil and with a little heat from the heatgun it finally agreed to vacate the crankcase... Next I went back to the sleeve gear. Last time I tried to make the bushes I wasn't careful enough with my measurements and turned the bronze down too small. I worked out that it needed to be 18.05mm on the outside, and decided that it would be best to drill the inside of each bush out to only 12mm, and then drill and ream it to match the new mainshaft when it arrives from the US. I will do this with it clamped in the lathe chuck on the sleeve gear's bearing journal to ensure concentricity.
-
I totally hear you on that, not least because I've been trying to identify bits of other bikes my dad had in bits and it's difficult to tell, unless he happened to write on them with a marker pen what they were. I noted your advice about asking Lynn and I phoned him earlier this week and I'm pleased to say that as we speak a brand new mainshaft is en route to me. Thanks again for mentioning him. Unfortunately he didn't have any spokes, so I'm just going to go with the quoted lengths from the parts book and get Central Wheel to make some (and hope they fit!). There'll be more to report at the weekend - I've been doing other stuff for a week or so, but I'm going to have another crack at the paint. Also I have about 30 things coming from inmotion. I got my order in just before the website went offline - if you phone them (01784 440033) then they will most likely take your order over the phone, which is what they did for me.
-
Further thinking... I am going to do a trial run at putting a second bend in one of the spokes I have. Possibly I could mill a jig and use the press, to get them nice and even. I have just been digging in the scrap bin and found some bits of spoke. The rear ones are not stainless, and I don't know if they're original, but I have found a few that look a little like the ones in Lorenzo's photo. I can measure the bend in them anyway, unless anyone has some genuine Bultaco ones they can measure. I am also sending the photo to Central Wheel to see if they've ever come across this before.
-
I have some Bultaco spokes here (not the right ones) and I see it's 4mm diameter at the hub end, and 3.5mm at the thread.
-
In my book they are 192, 165 and 167. Also it says M3.5 x diameter 4 (rather than the other way around). For the nipple it says M3.6, but maybe this is a typo. Central Wheel have asked me to provide measurements, so I'm not sure what to ask for. They give guidance on how to measure spokes, but who's to say Bultaco used the same method!
-
Great, thanks. Really I wouldn't expect anything less from those guys anyway. I think that's the decision made then!
-
From what I can see it will cost me around £200 to have a pair of Bultaco fork legs rechromed/refurbished. And that's assuming they can deal with the taper at the top for the fork yoke (early Sherpa). Or I buy new ones for half that price from inmotion. Are the inmotion ones likely to be of a comparable quality/tolerance? Anyone else bought them and have an opinion? Presumably they are a pattern part and not genuine old Bultaco stock. Thanks!
-
Wow looks like you really had some work to do! Looking good now though. Funny that you had a near identical paint spraying incident. I definitely learnt a lesson there. I do indeed have some gearbox wear, see below Yes it seems the ones with the double bend (see Lorenzo's post) are the problematic ones. I do have some packets of spokes kicking around, genuine Bultaco ones, but I don't think any of them are the ones I need. Today I managed to use a hybrid of two bearing puller sets to get that last 'blind' layshaft bearing out... Then I got to looking at the mainshaft and sleeve gear, with a view to making new bushes... However I found the wear on the end of the shaft to be uneven to the point of having quite a taper on it. I invoked questionable engineering practices and set about trying to grind the shoulder so that it was consistent for the length of the outer bearing, mindful that the shaft looked hard chromed and there wouldn't be much thickness to play with... ...and ended up going through the chrome. There was virtually nothing left anyway. So that pretty much consigns the shaft to the junk pile. I have two other engines I could use bits from but both have a different (later) type of shaft. One even has needle bearing races for the sleeve gear, so presumably Bultaco did learn. I do have a complete M49 engine which I could strip down, but something tells me the main shaft will be equally worn.