Honda cb175k6, 1972 re-build

[Terrotmt1]

Ha!
I've got some advice on the task in the USA, great forum for Honda Twins.
I cracked the same issue 5 years back and it was in those threads 5 years ago which a moderator had found for me to read.

Keep my mind off a dentist visit tomorrow reading that lot, but it will be fixed soon.

Best bit is the electric starter, no endless kick starting action. My knee still hasn't recovered from the French Follie.

Anyway, good to see your advice has not changed over the years!

[mini-me]

But you have a sense of  humour to get you through, something sadly lacking on nearly all old bike forums.

[Rex]

This is very true.
Some dohbait on another group has a B31 with a worn out clutch chainwheel, and his mate told him that he can fit a Suzuki clutch so he was asking the WWW how he could do it.
Got quite arsey when the general opinion was a) yer mate's talking bollix, and b) why not fit another BSA part and keep om chugging along for another 60+ years?

[TGR90B]

Funny you blokes should mention that, I find any humour severely lacking on sites these days. Considering that 50% of posts are rubbish, I would have thought more laughter would be appropriate.

[mini-me]

My mate says................



when I had my bike shop that was far as it got, rude interruption then said fek off and get your mate to  fix it.


I think you'll find Rex that there is a growing element amongst the  know it all younger than us that believe that if you fit enough new technology to an old bike it will miraculosly become a new old bike.

That have not cottoned on that new tech has not yet lasted as old   tech.

[Terrotmt1]

Think I've got it today.
Stripped the carbs for the 8th time, cleaned and cleaned again, poked all the holes etc and re-assembled.

It started just like that, instant on the electric starter and I warmed it up.
Had the usual hot side/cold side and it almost switch over sides during some tweaking, BUT I seem to have found a sweet spot.

The tick over is close to a Harley though the tacho says 1800 sounds more like 3 rpm to me.
The pilot screw seems close to redundant but has with some combination of throttle slide adjustment seem to have bought the engine to balance, the silencer temps are really close.

Boyed by that, the next step is to fit the air filters and see if things are all ok after and re-tweak. These little bike can be sensitive I've read to the choking effect of the cleaners, but I hope my custom foam ones will win through.

Number plate arrives tomorrow, seat on and IT IS FINISHED. 

(As if...)

[TGR90B]

Well done mate, or  until the next time. Dada dada dada, Just when you thought it was safe.

[Terrotmt1]

Thank you.
With this one coming to a close, I doubt I will get a chance to ride it anytime soon, so that may be 2021..

Not sure what to do for a project next. Hard to find a project of this type to consume time and give interest that is small enough to squeeze into the garage.
Pause for thoughts.

[chaterlea25]

Hi Terrot,

The pilot screw seems close to redundant

In that case there's still problems with the carbs,
Not having them in my hands to see how exactly they are laid out but "lack of response to the pilot screw adjustment" is usually down to one of the passages from the jet / screw up to the bore of the carb
There are usually two tiny passageways, one comes up just on the engine side of the throttle slide and maybe under the edge of the slide nearby
Years ago I worked on a lot of CD 175's and SS125's (single carbs) They always ran best on the book setting
I also found that those Keihin carbs worked extremely well on Triumph Tiger Cubs again altering anything from the Honda book setting resulted in poorer running

John

[Terrotmt1]

Yes, take your point.
It is running, but maybe not at it's best!
There are 3 small drillings to the pilot. The long one from the pilot to the small hole just behind the slide is clear on both and easy to poke through (I'm using BOC gas welding tip cleaning wires).
However, there are two shorter ones that you cannot get to unless you remove the small ball bearing seals, and those could be blocked.
No idea how to clear them. Both carbs have been in a small US bath for hours before all this kicked-off.

Maybe a professional US bath is needed?

[TGR90B]

Soak 'em in thinners for a couple of days and use a high pressure air nozzle.

[Terrotmt1]

Yes, I now have a doubt in my mind about the drillings thanks to John! 
There is one that is about 8mm long, drilled and sealed by ball bearings right in the heart of the body for the air ratio pilot screw and I have to get that sorted now.

I've cleaned old Porsche weber carbs (huge things) in thinners soaked for a week and that seemed quite good but the drillings are far larger dia.

Plan is to strip them and take the bodies to Villiers Services close to me and get them to US clean as they would for their carb rebuild service, and, as you suggest a weekend in thinners will finish the job.

As an expert ow on French and Japanese carb stripping it won't take long. Practice makes perfect and this will be the 9th time the carbs have been apart....

[Rex]

I found this for you to work on as the next project-

https://www.ebay.co.uk/itm/Vintage-Classic-motorcycle/143811112843?hash=item217bcf6f8b:g:lZ4AAOSw8GZfmb9v

It ticks all the boxes, French, two-stroke, old, no spares but very attractive in a Gallic sort of way. Looks younger than 1940 to me though.

[iansoady]

It does have a certain je ne sais quoi.....

[Terrotmt1]

I think my next project is the hall stairs.....

The carbs could not be cleaner!
Brake cleaner shoots through all the passages and jets, and to top it off they spent time in the US cleaner at Villiers Services this morning.

Bike running on equal heat both sides and a low tickover. I don't trust the tacho's accuracy.
Good response to the twist grip so leaving it all at that.

The air screws STILL do nothing around the 0.5 turn to 2.5 turns to the tick over.

The starter chain/sprags etc make an awful din now but sometime hook up and spin the engine well to start, so taken the generator cover.case off.

The chain is very slack, but i doubt it would go on if I took a link out.
Are they supposed to look 'too slack'?
The lower half is nearly touching the engine case.

I have new sprags etc coming, but maybe I should bite the bullet and fit a new chain while in there.

Oil came out black, so discarded.

Last snag to fix is the leaking lh side fork.
Fork oil keeps on coming out albeit very slowly. Seems to be coming from where the front mudguard mounts. Maybe the fastener hole has broke into the lower fork casting?

Anyhow, still progressing.