tci ?

[650mark]

will a tci from an '81 xs1100 work correctly in an '80? thanks

[DGXSER]

Not really. no. The 80 models used the 2H7 TCI and the 81 used the 4RO.

In 1981 Yamaha removed the mechanical advance from the timing setup and programmed it into the TCI. The 4RO TCI. If you use that TCI with your timing setup your mechanical advance will screw up the timing. Any 2H7 year TCI will work for you, 1978 through 1980 Standard or Special model does not matter.

[TopCatGr58]

Hey Don,

If that's the only spare TCI he has, couldn't he lock down or remove the cent. adv. mechanism so that he wouldn't be getting the extra timing advance affect!?

The 78-80 TCI's are much more common and not so $$, so I would think he would want to get one of those instead....or build his own....there's a tech tip using GM parts about it.

I also know of a couple of folks who have used the 81 TCI in an XJ, still worked fairly well, they just didn't get the vac. adv. fuel economy function, but otherwise had full power!

T.C.

[DGXSER]

Good Point TC. Certainly you could find a way to lock the mech down, or even remove it.

If the 81 TCI is all you have, the bike will run on it I am sure, I suspect just not very well at speeds if you did not lock down the mech adv.

In this case, it seems Mark might have the $$ rare 81 TCI, and need the cheaper easier to find 2H7 TCI. So he could possibly make money on the exchange! I know I sold a 4RO TCI for about $100 a couple years back. There is an untested 2H7 unit on fleabay right now for $32, more than a few less than $50.

Now if you saw the $10 81 TCI on fleabay, look close, that is for an XS650 not an XS1100.

[BA80]

Why not just get the correct TCI and fix it right? 2H7 TCI's are pretty common and all over fleabay. There' someone else I'm certain can use that 4RO. Hell I'll give you 2 2H7s for that 4RO.

[650mark]

thanks for all the info guys, but i only want a spare tci unit for my '80 special. had a chance to buy one for an '81 but i'll wait and find another 2h7 unit.

[LoHo]

Mark, I think I have one I purchased when chasing my no-spark, which had nothing to do with the TCI, by the way.

[650mark]

if it's for sale, how much? thanks

[LoHo]

I bought it from Ebay over a year ago for 100, I'll mail it to you for 75. I cannot verify that it works, but if not, I'll gladly refund your dough. I was trying to solve a problem and was eliminating possible sources by buying parts.

For then record, it's TYPE TID14-01 2H7-10.

If you want it, PM me your addy and I'll get it in the mail.