I've recently invested in an MC21 for restoration and whilst it seems mostly original and no major problems, the carbs are both TA21 (standard jets) and not TA22. I've had a look at the specs in the technical section etc and there doesn't seem to be much between them, but I'd welcome any guidance i.e. do they need to be changed to TA22 types?

I don't intend to make any modifications initially (get it working properly as a standard bike first), but I will probably look at the airbox & wiresplice mods once the bike is back on the road and useable.

Any advice is appreciated - thanks!

where in chesterfield are you mate? i am from taaarn as well
_________________
ive seen more tarts than mr kipling

hi mate, I'm in Hasland - you?

The engine is definitely the right type for the bike - round cylinders/wet clutch. Waiting for the dating letter from Honda...

Rest of the intake system looks standard MC21 (air solenoids/chambers etc), just a bit odd that TA21 carbs were fitted. It had the KISS cdi unit fitted as well but not sure if that is linked or not.

in newbold mate
_________________
ive seen more tarts than mr kipling

Done a bit more research and it 'seems' the only difference between the TA21 & TA22 carbs is the engine they are designed to work with. I could be wrong (and I don't have any TA22s to compare against), but it seems the castings/carb bodies are the same, linkage is the same, and so on. Basically the same carb - only difference I can see is that the TA22/MC21 spec carb is tuned differently for each cylinder, instead of the same settings for both with the MC18.

Does that sound right? Anyone know for sure?

Still not sure why my MC21 had TA21 carbs fitted, but going to work with them anyway.

Question is - block the PWJs or not? Easier to tune if you are making modifications? Does the same apply to the air-solenoid/chambers as well?

Not being an expert, I knew there was some info on the site but forgot where it was. Details of carbs is here http://tech.nsr-world.com/nsr250/all-nsr250/nsr250-stock-carb-settings.php
MC21 has a gear indicator. I expect the carbs and PGM are used to restrict. I assume your KISS PGM and TA21 carbs provide a good derestricted setup without needing a wire splice
_________________
Why do things simply when you can complicate them

I remember discussions and good explanation on power jets before. Try the search option on the forum, but I think it relates to HRC kits and track tune
_________________
Why do things simply when you can complicate them

Thanks RobH - I'll do some more reading

TA21 and TA22 carbs are different. TA21 can be made to work, but it's not just as simple as swapping jets, as the internal galleries are different.

The differences are very small, but under the right conditions can make a significant difference.

My advice would be to souce some TA22s. Play with the TA21s as and when you feel you know the fuelling and air correction characteristics better.
_________________
Andy.
NSR-WORLD.COM

Please keep all responses to Forum posts on the Forum so that others may benefit.

Please DO NOT PM me for technical advice. My time is precious, and you will probably receive a faster response on the Forum anyway.

Check us out on Facebook! Please "like" our page!

Thanks Andy, that seems like the safest option...

Andy did you have any comment on the KISS PGM? Just wondered if it might be specific to the TA21 carbs?
_________________
Why do things simply when you can complicate them

No, the KISS CDI is universal. It's just a wire splice in a neat box.
_________________
Andy.
NSR-WORLD.COM

Please keep all responses to Forum posts on the Forum so that others may benefit.

Please DO NOT PM me for technical advice. My time is precious, and you will probably receive a faster response on the Forum anyway.

Check us out on Facebook! Please "like" our page!