CB175 performance advice

[Romeo]

Gidday guys,
I'm not having problems per se, I'm just wondering if I'm getting all that I can out of my '72 Honda CB175. The Old Man's pretty concerned that she can't really muster 100kph+ on the open road - and it's pretty frustrating tbh.

So, I'll just explain a few issues I'm having with it and see if anybody can recommend a course of action. Though bear in mind I'm no mechanic, so go easy on me!

1) It's using a bit of oil, I usually have to top it up after every 150kms or so.
2) It's making a quiet popping/backfiring noise almost constantly.
3) There's often an oily black residue at the end of the pipes.
4) Doesn't want to go over 100kph+, even though many accounts overseas say it'll do it no sweat.

Are these anything to be too concerned with?
Am I simply asking too much from an old bike?
Is there a likely culprit that's a quick-ish fix?
Should I just live with it and trade up ASAP?

Ideally I'd just like to get an extra 5kph topend on it so I can flow better with traffic!


Cheers,
Any advice welcomed!

Romeo

[Ixion]

FFS it's 36 years old! It's a wee teeny tiny itsy bitsy bit worn out.

CB175 should hit 70mph (120kph) easy as . Oily residue and popping, rings are worns , valves are leaking. Pull the head and barrels (easy peasy on those bikes) call the magic dudes at Econohonda and get new rings (maybe new pistons, get an engineering firm to advise), and grind the valves. It'll be just like a new one, good for another quarter million ks.

[Romeo]

Oily residue and popping, rings are worns, valves are leaking. Pull the head and barrels (easy peasy on those bikes) call the magic dudes at Econohonda and get new rings (maybe new pistons, get an engineering firm to advise), and grind the valves. It'll be just like a new one, good for another quarter million ks.

Hey, thanks a lot Ixion this is EXACTLY the advice I was after! Might have to get my delicate IT hands dirty for once.

//EDIT: As long as I source all the parts, does anyone have any idea on how many hours should it take a qualified mechanic to complete the job?

[vifferman]

FFS it's 36 years old! It's a wee teeny tiny itsy bitsy bit worn out.

Ohhh! So that's my problem! (I'm olderer'n 36, BTW...)

CB175 should hit 70mph (120kph) easy as .

Ayup.
Had mine pinned at an indicated 85 a few times (with a slight downhill).
The worstest things on the CB175 (like many Hondas) is the camchain tensioner. If it gets noisy, fix or replace it. Otherwise it's pretty reliable.

[Coldrider]

Don't forget to fit upswept megaphones.

[Romeo]

Pull the head and barrels, get new rings (maybe new pistons), and grind the valves.

Can anyone tell me how many hours of mechanic labour I'm looking at?
I know a few mechanics who may be keen on helping out, as long as their all properly lubricated.

[ManDownUnder]

Ohhh! So that's my problem! (I'm olderer'n 36, BTW...)

Yup - check your piss-tin immediately!

[Joliet]

As long as I source all the parts, does anyone have any idea on how many hours should it take a qualified mechanic to complete the job?[/B]

Umm, ask pops? Payment in beers should do it, and it may take about 6 weeks to do but um .. easy and basically free? ..