1st gen/2nd gen trans swap

[Venturous Randy]

Ok, I have started the tear down of the spare engine that I got when I bought the 85. I was told that this 83 engine had only 30,000 miles on it and after spitting the case, I really do believe it may be true. There is no doubt in my mind that the engine had never been apart since new.

One of the first things I wanted to see was what the gear dogs looked like on 2nd gear. I found that they had no noticeable wear at all. That was a good sign. Now, one thing that did surprise me was that the dogs on 2nd gear appeared and measured to be slightly undercut . I knew that later year 1st gens were undercut slightly, but I had never heard the 83's were. But, I have never looked at an 83 that did not already have a problem of being worn.

The second issue that does give me some concern is not only did Yamaha change the gear diameters and number of teeth, but they also changed the width of some of the gears, but it appears to be only in the gear teeth area, but not the width where it is on the shaft. In setting the gearsets beside each other, and I am actually comparing an 86 set with the 02 set, you can see the difference. So far it does look like that the gears will line up with the proper fork placement. The next step will be to put the 02 set in place and set the bottom back on with the forks in place and see if it shifts thru the gears ok and see if everything lines up.

I really do hope this is a viable option for the 1st gens, not only as a 2nd gear fix, but I want to have wider spaced gear ratios like the 2nd gens have. With also adding the V-Max rearend, 1st and 2nd gear will be slightly lower, 3rd and 4th will be about the same and 5th gear will be higher.

On the pictures, you can see where the 2nd gear dogs have no obvious wear and you can also see the difference in the gear widths. The last picture is with the bottom off the 83 engine with the original gears.

RandyA

Edited March 26, 2011 by Venturous Randy

[Reddog170]

From the pictures it looks like it will work out quite well. Will be following along to see how it goes. Shaun

[MiCarl]

The gear dogs are always undercut. That is so torque pulls them together rather than pushing them apart. As far as I know they've always been done that way.

[Yammer Dan]

Hummmmm!!!

[Venturous Randy]

Well, it looks like I have run into my first problem. When I set the gear sets in the bottom half of the engine where the gears fit into the forks, it appears the forks do not hold the gears in the proper alignment. When I have it in neutral, the dogs on some of the gears catch on the matching gear. When I shift into 3rd gear, the spacing is off enough that it is actually in neutral as none of the gears are engaging. When I pull the 01 trans out and sit the spare 86 trans in, everything lines up perfectly and shifts fine.

My problem is, I do not know if the problem is the forks or the drum or both that is different for the alignment to be off. I checked the part numbers on both and even though the numerical part numbers are the same, the 1st gens start with 26H and the 2nd gen is 4NK. My frustration is when I bought the gear sets, I should have asked for the other parts because I know he never sold them and I have no idea who I got the parts from.

RandyA

[rjyammy]

I bought a used gear set off an 88 Venture. I have a couple questions after looking at your pictures of your gearset. On 2nd gear, is there supposed to be a slight radius on the edge of the dogs where they engage or is it to be sharp edge? I see in your picture there is a radius, or is it worn? Also my 2nd gear is slightly discolored like yours in the picture, is this normal or from being overheated? Do i need to replace to be safe? I am in prcess of doing 2nd gear replacement. Does anybody know if i can buy the dust boot for clutch slave cylinder or do i have to but complete cylinder? Does anybody have a contact for bushings for rear suspension linkaqe? They are not very cheap where i have checked. I plan on joining club, you guys have really helped with all tech. Thanks.

[Venturous Randy]

Hey Randy, I see you have an 84 and that is one of the problem years. Actually, the less it is rounded off the better, but even on any of the used transmissions, such as the 88, there will be some rounded area. I bet that when you pull out your 84 gearset, especially if it is jumping in 2nd gear, it will be a lot more rounded than my pictures or the 88 you have.

As far as the boot on the clutch slave, I am sure there may be someone on here that has one, but if you need a dust boot, you probably also need a new slave anyway as it is probably corroded.

I am not sure about the bushings for the rear suspension linkage. Just make sure that when you take the rear suspension apart that you install grease fittings and that pretty much takes care of the squeaks. How worn are your bushings? I ask because the alignment and tightness of the rearend is in your bearings where the swingarm pivots , not in your suspension bushings. In my opinion, if they are a little worn and you keep them greased, you won't notice it.

One other thing on the trans swap. If you were already having a problem with your bike jumping in 2nd gear, I suspect you will also have the fork associated with 2nd gear being bent some.

Good luck, join our crowd and keep us informed.

RandyA

[Lil Venturous]

I think I would just buy shift drums first.

 

Anybody here got any?