My Honda CB100N project - “Rusty”

[billy sugger]

My cb125 used ATF,without any issues

[GojuRyu5]

4 minutes ago, billy sugger said:

My cb125 used ATF,without any issues

Thanks for that. Any thoughts on a specific type or would a generic ATF suit?  I’m seeing Honda DW1?

[billy sugger]

It was a generic ATF, probably about 5 weight. The bottle is still at my lockup,so I'll pop over and see

[GojuRyu5]

Decals arrived - not perfectly sized, but it does make the side panel looked finished.  This is the first of the two (paint still drying on the other since the re-working, and I still can’t strip the tank because the original owner still hasn’t ‘found’ the keys as promised… Waiting for locksmith to solve this for me.  But I thought I’d press ahead with the one panel I CAN do to get some practice on the cleanest surface.  
 

I think the main striped decal has come up a little short in length (or a little wide at its widest point) although it is equally possible that I haven’t lined it up correctly…, but it doesn’t really notice.  Overall, it looks decent, and so I’ll give it a clear coat once it’s dry to seal it in and that should be finished.  Nice to have that in place.

 

 

Edited September 2, 2023 by GojuRyu5
Spello

[GojuRyu5]

Also noticed that the air filter is missing its foam cover, so had to make one out of flat foam and make an appropriately sized tube.  Stuck nicely with carpet adhesive and fits snuggly.  Job done.

 

 

[GojuRyu5]

And to top off a full day in the garage, the frame has had a final rub down and the first three coats of red oxide primer.  Really felt that I made the most of my time today.  Mrs Goju was out so I smashed it. Absolutely stink now, so desperate for a shower, followed closely by a beer.  Beaulieu International Auto Jumble tomorrow!

 

 

[GojuRyu5]

Both panels done. Difficult to see the plastic repair. Pleased with the outcome.

 

 

Edited September 4, 2023 by GojuRyu5

[Fozzie]

Should have chipped in earlier, ATF is light stuff.

I'd suggest if you are heavier than the 17 year olds that used to ride these, 10w fork oil would be a good bet as an alternative. Previous bikes I've had that dive under braking and needed a lot of pre-load have been treated to a weight up from stock. Lets me back off on the pre-load a little and keep the ride smooth, as too much and you feel every bump. 

 

The little Honda's are generally quite softly sprung, if this is anything like the CG125 or CBF125, which both needed thicker oil in my view as they were very "bouncy", I'd go with the 10W fork oil. 

Edited September 5, 2023 by Fozzie

[GojuRyu5]

14 hours ago, Fozzie said:

Should have chipped in earlier, ATF is light stuff.

I'd suggest if you are heavier than the 17 year olds that used to ride these, 10w fork oil would be a good bet as an alternative. Previous bikes I've had that dive under braking and needed a lot of pre-load have been treated to a weight up from stock. Lets me back off on the pre-load a little and keep the ride smooth, as too much and you feel every bump. 

 

The little Honda's are generally quite softly sprung, if this is anything like the CG125 or CBF125, which both needed thicker oil in my view as they were very "bouncy", I'd go with the 10W fork oil. 

Thanks @Fozzie, that’s really helpful.  I’m DEFINITELY heavier now than I was when I rode this model in the mid 1980s, so that’s a useful consideration. Much appreciated.

[RideWithStyles]

Check the spring, is it still in spec after all these years?  What about the shocks? Ill be surprised if rhere is any dampening left.
 

Seeming as your heavier than what was thought the average rider would be back in the day might be good for the bike and youself if the spring is capable of not smashing itself (both through and the return stroke) by a pebble let alone a pothole, a stronger progressive spring might be worth while.

 

on another note. Yes using fork oil will be better than atf and starting at 10wt but dont be surprised if it still pogos and may require a thicker oil to control itself...

 

misses has a 125 with emulsion forks on 2011. 10wt the thing pogoed at a stand still , making a corner was a 20pence job at best with cold sweats even under 60kg weight and the tyre wear showed it.

 

We ended at 20wt for her as an big improvement but if it was up to me it would be a different spring with maybe a thicker 20wt from different brand to get that improvement from the stock kit or even a possibility going to mid 30s for her.
The next step which would be close up or block off one of holes in the "std valve" or better yet replace that valve for an aftermarket unit.

If it was mine id would be all that, then tweak the oil depending on how much adjustment the AM valve gives.

 

with you going all out for this bike you might as-well carry on doing it well and not fail with the suspension. 

Edited September 16, 2023 by RideWithStyles

[GojuRyu5]

2 hours ago, RideWithStyles said:

Check the spring, is it still in spec after all these years?  What about the shocks? Ill be surprised if rhere is any dampening left.
 

Seeming as your heavier than what was thought the average rider would be back in the day might be good for the bike and youself if the spring is capable of not smashing itself (both through and the return stroke) by a pebble let alone a pothole, a stronger progressive spring might be worth while.

 

on another note. Yes using fork oil will be better than atf and starting at 10wt but dont be surprised if it still pogos and may require a thicker oil to control itself...

 

misses has a 125 with emulsion forks on 2011. 10wt the thing pogoed at a stand still , making a corner was a 20pence job at best with cold sweats even under 60kg weight and the tyre wear showed it.

 

We ended at 20wt for her as an big improvement but if it was up to me it would be a different spring with maybe a thicker 20wt from different brand to get that improvement from the stock kit or even a possibility going to mid 30s for her.
The next step which would be close up or block off one of holes in the "std valve" or better yet replace that valve for an aftermarket unit.

If it was mine id would be all that, then tweak the oil depending on how much adjustment the AM valve gives.

 

with you going all out for this bike you might as-well carry on doing it well and not fail with the suspension. 

That’s brilliant, thanks @RideWithStyles. I have dismantled the forks and have a new seal kit, ready for the rebuild. I bought some 10W for now, and will see what it is like on rebuild; relatively simple to upgrade the oil if I have that same issue. Having not ridden a bike of this size for more than 30 years, a lot may also depend on my riding capabilities and the local roads.

 

I have also replaced the rear shocks as those weren’t serviceable and the chrome too far gone. I’m hoping that will mean the rear set up will be OK once I get the pre-load sorted.

 

As this is the first time I’ve done this, it’ll be trial and error, but I really appreciate the advice. It means that if it doesn’t feel right, I will have options. Thanks bud.

[GojuRyu5]

So the frame restoration continues. Family away for the weekend means time in the garage. Spray booth set up and frame ready for first top coat.

 

 

[GojuRyu5]

Also, thanks to a local locksmith (and £30…) I have managed to get a key for the ignition and it also has allowed me to open the flap on the petrol tank. So now I have been able to access the petrol cap, and can start the rust treatment / paint stripping / repainting.

 

Another problem solved.

 

 

[GojuRyu5]

Forks disassembled. Have set up my bench grinder with a polishing wheel, so will start by giving the lower parts a good clean before reassembly.

 

 

[Fozzie]

Are you bringing the forks to a chrome finish? Would probably suit a bike of that age, but I can see it being irritating to upkeep if you decide to keep and use the bike all the year!

 

I'm gearing up to really break ground on my CBR125. Just waiting on the V5 to arrive for a new frame I bought for it (deals with the write off issue using a clean frame). But the forks will have to go black as a new old stock swingarm I bought is black so will need to match. But on my ER5, I'm between chroming and painting the forks, so I will watch how you get on and make a judgement call. The ER is going to be a scrambler, I just haven't decided if I style it towards being a tough mudder, or like a Ducati scrambler, a show piece for the road that's styled that way. 

 

Even though the engine on this bike will be light, I'll be tensing up on your behalf when you put that back in the frame! Nothing worse than that one little wobble, and seeing a small chunk of paint fall to the floor. 

[GojuRyu5]

Thanks @Fozzie. I’m going with chrome finish on both front and rear shocks. The new rear shocks I bought are almost identical in design but they’ll definitely look better with a chrome finish on this age of bike.

 

Front forks have been disassembled, so have given the lower parts (is that the fork ‘legs’?) a good clean and polish before reassembly - they’re not perfect, but have come up OK. I got the seals out (one was completely rusted in indicating an issue with the dust cap which I’ll also need to address).  On this vintage of bike, chrome front forks will definitely look better.

 

Edited September 18, 2023 by GojuRyu5
Spello

[GojuRyu5]

The frame has taken the paint well and looks 1000% better than it did to start with:

 

But @Fozzie now you’ve made me nervous about remounting the engine . Fortunately, I still have a way to go before I cross that particular bridge as I want to get the rolling chassis sorted first and the rims have not yet come back from the re-chromer.

 

Having now got a key, I have been able to strip the paint from the tank and remove the decals, so I have plenty to do whilst I wait for the parts to come back.

[Ian Frog]

Hi 

Great work so far and definately enjoying seeing the progress.

For remounting the engine there are a couple of things you might like to consider.

1. with heavy engines I tend to put them on their side and bring the frame to the engine.

2. If the above is not possible or practical the old foam pipe lagging and plenty of gaffa tape come out.

Good luck either way.

Cheers

Ian

[GojuRyu5]

On 18/09/2023 at 13:06, Ian Frog said:

Hi 

Great work so far and definately enjoying seeing the progress.

For remounting the engine there are a couple of things you might like to consider.

1. with heavy engines I tend to put them on their side and bring the frame to the engine.

2. If the above is not possible or practical the old foam pipe lagging and plenty of gaffa tape come out.

Good luck either way.

Cheers

Ian

@Ian Frog, that’s a great idea(s), thanks. This is my first restoration so learning ‘what not to do’ and the tips of others is most definitely of value.  The thought of losing the paint finish by virtue of clumsy handling of an engine is a nightmare.

 

So, given your first comment about bringing the frame to the engine, do you mount the engine early in the rebuild process bringing a heavy bike to an engine seems to have the same challenges. In this case, the CB100 engine isn’t too heavy, so manageable, but I’d say a two person job.  The pipe lagging and gaffa tape comment is on point if I take this approach. Still got time to think about that one fortunately, but you guys are amazing with the tips. Thanks bud.

Edited September 23, 2023 by GojuRyu5

[GojuRyu5]

4 hours ago, Fozzie said:

I'm gearing up to really break ground on my CBR125. Just waiting on the V5 to arrive for a new frame I bought for it (deals with the write off issue using a clean frame)

Fozzie, (or anyone else for that matter), can I ask about this point.  I bought the bike without an engine, and have sourced one separately. I have the engine number from that and the original bike’s frame number is on the V5.  I was assuming that I would have to reach out to the DVLA to get the engine number included on the V5 moving forwards, but is this straightforward? Any thoughts or advice on that?

Edited September 18, 2023 by GojuRyu5

[RideWithStyles]

Pretty much as long as you've got the doc for them both or good reason (reputable dismantlers/scrap yard record for the engine) or suspect that its not from a stolen bike, the dvla wont be that fussed as long as you fill in the forms to let them update the records and give you a new piece of paper.

[GojuRyu5]

3 minutes ago, RideWithStyles said:

Pretty much as long as you've got the doc for them both or good reason (reputable dismantlers/scrap yard record for the engine) or suspect that its not from a stolen bike, the dvla wont be that fussed as long as you fill in the forms to let them update the records and give you a new piece of paper.

That helpful. Got it from a well established motorcycle garage / mechanic in Plymouth via eBay so I had better retain some evidence of that transaction before it disappears. Thanks matey

[Fozzie]

23 minutes ago, GojuRyu5 said:

Fozzie, (or anyone else for that matter), can I ask about this point.  I bought the bike without an engine, and have sourced one separately. I have the engine number from that and the original bike’s frame number is on the V5.  I was assuming that I would have to reach out to the DVLA to get the engine number included on the V5 moving forwards, but is this straightforward? Any thoughts or advice on that?

 

Get a V62 and fill out the details, you only need a frame number. For some reason they aren't fussed by the engine number at this stage, and at the moment I'm unsure why.

I suspect when I get the V5 it will have the old engine number for that frame on there, and if it does, I just send it off and explain "engine was toast, so I bought a second hand one with the following number". But there's also the chance they just didn't have it originally, so aren't too fussed. 

 

If you don't already know, applying is £25 by cheque or postal order. Make sure you send it recorded delivery, and be prepared to wait. As if the bike was originally sold to a scrappy without any paperwork, the DVLA will reach out to the old owner and give them a few weeks to reply. And then they send you the V5. Once I get mine, I'll be able to comment on the engine number. 

 

Problem I have is I've also changed the colour of the bike, so I'm expecting some questioning from them

[RideWithStyles]

.

they should have filled out paperwork when they acquired or stripped parts and sent them off but assuming is the mother of cock ups, further more with paper trail of the supposed next owner and you get the paperwork to fill it in but rarely online sellers do it so you better off just making sure its done.

otherwise a reputable garage will flag up problems at mot time.

if the police pull you over for something and bother to check (especially if uve been naughty) they will try to trace and copper gets annoyed at have to spend more time small talking while following up loose ends.... as they will think " is it a stolen engine, why doesnt the docs follow up....

[GojuRyu5]

34 minutes ago, Fozzie said:

Problem I have is I've also changed the colour of the bike, so I'm expecting some questioning from them

Rats, I’ve done the same