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'78 TT500 shifting problem

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Hello, I am making my 2nd post, and seeking info from anyone who has encountered this: This 1978 TT500 I bought last fall was ridden up the road and went through the gears from what I remember. I was watching, not riding. So I bought this from my friend and started to purify it a bit. I got it started (not my strong suit for sure!) and rode it up the hill and back. I could not shift it out of 1st or even get it back into neutral. I have it on the stand, and am inclined to have a look in the primary side and inspect the shift indexing system before pulling the engine. I will regret that, as it has such great compression after apparently having recent top-end work done, I just hate to take it clear apart for a gearbox problem if it can be solved through the primary side. I've never bought into the "bent" shift fork thing, as I know they are brutally strong, at least in my opinion, but that is one thing I'm hearing from different camps. Following is my 1st post about a similar problem with a '75 DT250 that cleared up after a few minutes of riding:

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Hello, this is my first post, so don't beat me up too bad! I have a DT250 ('75) that was working perfect this past fall (4600 miles), and after sitting for 4 months it started not shifting any further than 1st to 2nd. After some riding around starting in the yard and then out on the road, it finally stopped malfuntioning. I amd looking for input as to what may have caused this, and I also have a '78 TT500 that is not shifting at all and it did last fall, although not very good. The DT is fine now, I'm going to change the gearbox oil, and as for the TT, post this in the appropriate (although there does not seem to be one for TT500's) forum, and see what they say. My incination is to have a look at the indexing mechanisim on the TT, and see if I really need to pull the engine to fix the gearbox. Thanks for any advice, Tarzy

So if there is any advice from one who has been here before, problem-wise, I am all ears! Tarzy

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Is the shifter locked in one position, or does it move up and down freely with nothing there, like, moves down and stops and moves up and stops?

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I forgot to mention the clutch is not the problem; the problem is occurring on the stand.

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The shift shaft is not stuck, but acts like the "picker" cannot move the Shifter Drum; almost like the Drum's stuck. That is why I was thinking of exploring the right-side's innards. My DT250 started working after a half mile of riding, and essentially was doing the same thing. I have encountered water (condensation) in my floats on some bikes during the winter, but have never heard of it getting into the shifting components. Also, I've never heard of "bent" parts inside, except in a few extreme cases. My M/C experience is from the past racing a pair of TZ250/350s in AMA and I did all my own engine work, cranks and all included. My prior experience was only hobby oriented, but I am also retired out of racing Porsches and Ferraris for a little over 23 years.

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There is an adjustment for the shifter where it goes through the center case below the clutch. I've heard of this giving problems when it's not set right. If you have a book on the bike it explains the procedure for setting it up the shifter engagment.

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The shifter mechanism is under the clutch cover but the forks and shift drum are inside the cases.

Check the mechanism and look closely at the end of the shift drum where the index pins go in. Mine broke a section of the drum away and dropped one of the pins. It would change up but a downshift from 3rd to 2nd went passed

2nd and into neutral.

What gear is affected will depend on what part of the drum is broken, IF this is the problem.

Brent

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