They are still out there.

[John Orchard]

So about 5 years ago my Missus brings home a TS185A ('76) engine complete (with carbs, pipe & electrics) in a bare frame from the tip where she use to work, I spray a bit of Start Ya Bastard in the carb; runs for a couple of seconds, heaps of comp through the kick lever. So I tuck it away down the back corner of the shed, I thinks to myself "that might come in handy one day".

So I just tore it down, it's never been apart before, std bore still with cross-hatch in the bore, no blow-by past the rings, it needs NOTHING, everything is like brand-new inside, I am truly amazed !

I have a TS125B rolling chassis, might see if it will fit (even if it doesn't, it will ;-) ) ........ Now where's that porting tool ;-)

[sleepy]

Might need a new set of crank seals after 46 years.

[John Orchard]

Might need a new set of crank seals after 46 years.

They feel as soft as a new set.

[TT5 Matt]

you'll need to relocate the bottom back engine mount to fit it into the 125 frame and make up new front engine mount plates.with my 185A i raised the exhaust port 1.5mm and took the inlet out from 26mm to 32mm,i also dedagged the transfers and opened up the rear boast ports as there very choked up.i also filed the sides of the exhaust port out to the steel liner.you can fit a tm250 rotor/stator for a faster reving motor and tm/rm125M/S gearbox for better gear ratio's

[John Orchard]

you'll need to relocate the bottom back engine mount to fit it into the 125 frame and make up new front engine mount plates.with my 185A i raised the exhaust port 1.5mm and took the inlet out from 26mm to 32mm,i also dedagged the transfers and opened up the rear boast ports as there very choked up.i also filed the sides of the exhaust port out to the steel liner.you can fit a tm250 rotor/stator for a faster reving motor and tm/rm125M/S gearbox for better gear ratio's

Thanks Matt, good info. The biggest hassle with fitting the TM/RM gear is finding it ! I'll do a bit of port work, beef up the clutch, fit a VM32, make a chamber (of maybe make a PE175 pipe fit?). If a TM250 stator was found, would I need the TM CDI unit also? If you remember other good mods that you have done, please keep me updated, thanks :-)

[TT5 Matt]

im still using 185 sparks as i only use the bike for circle work but id say you would use the tm125 cdi with the 250 rotor/stator but ask Cycle God as he fitted a 185 into a tm125 roller with a 175 hop up cyl and 32mm carb which he said worked well as far as jetting was concerned out of the box.another cheap carb option is a early single cable 29mm oval bore carb for a er185 B/C.he also used a 185 hop up pipe which are like rocking horse poo to find now days.with porting i use old chain saw sharpening files i found out the dump and bend them using heat for dedagging transfers/inlet.Doc said about turning some metal off the stock rotor for a faster revving motor and could be alot easier to do than find tm250 sparks just dont take too much off where its needed for strength.

[John Orchard]

im still using 185 sparks as i only use the bike for circle work but id say you would use the tm125 cdi with the 250 rotor/stator but ask Cycle God as he fitted a 185 into a tm125 roller with a 175 hop up cyl and 32mm carb which he said worked well as far as jetting was concerned out of the box.another cheap carb option is a early single cable 29mm oval bore carb for a er185 B/C.he also used a 185 hop up pipe which are like rocking horse poo to find now days.with porting i use old chain saw sharpening files i found out the dump and bend them using heat for dedagging transfers/inlet.Doc said about turning some metal off the stock rotor for a faster revving motor and could be alot easier to do than find tm250 sparks just dont take too much off where its needed for strength.

I didn't know the ER185 has an oval bore carb? I'll check one out. Yeh thought about turning-down the outside of the stock flywheel, I'll see how it feels stock first.

[tony27]

Not that hard to do an oval bore carb, have a couple of 30mm Oko d-slide carbs that use the 28mm body then offset 2mm towards the top & use the same setting on the boring head. The bore is technically more a figure 8 & behaves like a 28mm at lower openings but wide open is 30mm high by 28mm wide

[John Orchard]

Not that hard to do an oval bore carb, have a couple of 30mm Oko d-slide carbs that use the 28mm body then offset 2mm towards the top & use the same setting on the boring head. The bore is technically more a figure 8 & behaves like a 28mm at lower openings but wide open is 30mm high by 28mm wide

Yep I oval bored the 29mm flatslides on my '85 GSXR750, heaps more top-end :-)

[TT5 Matt]

interesting,i'll do that oval bore mod to my stock 26mm twin cable carb as it's working really well so will i need to up the size of the main jet to compensate for the increase airflow?

[John Orchard]

interesting,i'll do that oval bore mod to my stock 26mm twin cable carb as it's working really well so will i need to up the size of the main jet to compensate for the increase airflow?

Yep, probably only by 10 I reckon?