Bultaco Model 49

[David green]

Hi Chaps I am looking for info on my M49 which I purchased in 2016. What I know so far is it was first registered by Sid Moran LTD (Windsor comp shop badge still attached to rear mudguard) on 16th October 1969.Reg No MPP8H frame No B4900477 engine No a few digits earlier. It was then sold to Robert John Swift on 29 October 1969 who appears to be the only owner until I purchased it. Not sure why frame is yellow but removed some of the paint and it doesn’t appear to of ever been silver. Am not going to restore it but use it as is as it just looks so good with all its battle scars. Am looking for any information on the bike or The Rider Robert Swift. Regards all David 

[feetupfun]

Looks like a mechanically standard series 1 model 49 and yes the patina is excellent. Great to see. Thankyou.

I'll bet the seat foam is rock hard ?

[WJSmith]

oh wow that is ? real beauty that. I would ride as is. Lovely purchase

[delberto]

My work in progress! Barrel is damaged but I have a spare waiting on a rebore after lockdown. Needs tidying but runs  and starts well with mikuni. frame number B4900444 engine number is higher but closer to your frame number, is it true they weren't matching at the time because of tax reasons?

Edited May 16, 2020 by delberto

[David green]

I heard it was because they came in kit form from importer 

[woody]

Yes, the engines were removed by the importer and the bikes sold as kits to avoid purchase tax. The frame and engine numbers couldn't match to qualify as a kit so frames and engines were mixed when they were sold which is why they never have matching numbers up to the point purchase tax was abolished in 1973. From then on they were sold as complete bikes so numbers would have matched from new

[woody]

3 hours ago, delberto said:

My work in progress! Barrel is damaged but I have a spare waiting on a rebore after lockdown. Needs tidying but runs  and starts well with mikuni. frame number B4900444 engine number is higher but closer to your frame number, is it true they weren't matching at the time because of tax reasons?

That's a small rear sprocket which will make the gearing very high, standard gearing is 11/46 on a 520 chain. It looks like a later wheel with conical type hub is fitted along with later forks and yokes. Shock top mounts have also been re-positioned slightly lower and forward and gussets added in front of them  (not criticism, just observation)

You might want to consider re-routing the wiring out of the casing bottom and move it higher to the front as on later bikes as there is always a chance it could get crushed between the bashplate and engine and break with a hard hit on a rock (common on Ossa MAR)

[delberto]

54 minutes ago, woody said:

That's a small rear sprocket which will make the gearing very high, standard gearing is 11/46 on a 520 chain. It looks like a later wheel with conical type hub is fitted along with later forks and yokes. Shock top mounts have also been re-positioned slightly lower and forward and gussets added in front of them  (not criticism, just observation)

You might want to consider re-routing the wiring out of the casing bottom and move it higher to the front as on later bikes as there is always a chance it could get crushed between the bashplate and engine and break with a hard hit on a rock (common on Ossa MAR)

if there is a chance the wiring gets crushed under the bashplate i hope i am not on the bike at the time!

[section swept]

1 hour ago, woody said:

That's a small rear sprocket which will make the gearing very high, standard gearing is 11/46 on a 520 chain. It looks like a later wheel with conical type hub is fitted along with later forks and yokes. Shock top mounts have also been re-positioned slightly lower and forward and gussets added in front of them  (not criticism, just observation)

You might want to consider re-routing the wiring out of the casing bottom and move it higher to the front as on later bikes as there is always a chance it could get crushed between the bashplate and engine and break with a hard hit on a rock (common on Ossa MAR)

Lower frame tubes have been removed, check the engine cases for damage due to frame tubes being forced into contact. With vibration this can wear the cases on the undersides or even crack them. Convoluted air hose not good for uninterrupted smooth air flow. None of this is criticism just my observations. Good luck with your Bultaco enjoy the ease of working on her.?  

[delberto]

yes all good points and is a wip.

Woody i have the correct wheel i think, but am short of a brake plate i will start a new thread as don't want to hijack this thread and see if you can id it. 

thanks

[David green]

After a quick spin yesterday it would appear that the front forks need a rebuild but that’s about it 

[woody]

2 hours ago, delberto said:

yes all good points and is a wip.

Woody i have the correct wheel i think, but am short of a brake plate i will start a new thread as don't want to hijack this thread and see if you can id it. 

thanks

The fitted wheel looks in good shape so no point changing it for the sake of it really. The older type wheel is a heavy lump of a thing fitted to bikes from 66-73 but it may have varied slightly in design through the model range even though they all look the same, I'm not sure, so finding the correct brake plate may be tricky. Hub diameter, brake shoe width may vary etc.  I'd leave that one in myself, I have that type wheel in my own 49

[woody]

1 hour ago, David green said:

After a quick spin yesterday it would appear that the front forks need a rebuild but that’s about it 

You don't mention what's wrong with the fork action but when you rebuild, 180cc max of 10W fork oil is a good benchmark, start with 160cc and add a bit as necessary. These old forks won't damp very well if you use thinner weight oil

[David green]

There leaking oil past the seals