Nyper build thread

[Nikolai]

Talked to dealer buddy, clutches are not suppose to be centered at rest and the little bit of offset towards the chassis is correct. I will stick with 15mm offset.

 

[Nikolai]

Because the front section of frame pulled up a little when welding I had to space the motor up to get adequate clearance to the tubing. I only had to space it up .063

Side clearance to tube

With motor locked in place and clutch offset dealt with I can start on mounting the drivetrain. Weight target for drivetrain mounts is under 2 lbs.

 

[kinger]

Correct on offset being off while stationary and it centers up on the floating secondary while under load. Sorry I'm late to the party. Warping while welding the thin tube is something I hadn't thought it. Looks like you figured it out, nice!

 

[Nikolai]

Got motor property aligned and parallel with the secondary. Bolted the exhaust back on to make sure nothing had to change from raising the motor slightly.

Trying to think of the best way to finish this out. I think I’m going to cut and tack weld only the front motor mounts to keep it from moving while I take the primary off and on. Once the front mounts are tacked and motor bolted so it can’t move I can get the jackshaft set at 10.57” c to c and do the drivetrain plates. Once the drivetrain is done then I think I’ll remove the frame, weld it out again then put it back in the jig and do the rear motor mounts.

 

[Nikolai]

Front motor mount tabs done. Used .090 4130 plate. Total weight for all 4 tabs only 0.38 lbs which is under my target.

Bent sides out on Mag side mount so weld wouldn’t be in only a straight line.

PTO side bracket I tied into both 1” tubes for additional strength.

Felt the outside tabs were strong enough to just do basic tabs on the inside.

Eventually I’ll get (4) M12 x 75mm Ti bolts, washers & nuts and for the motor.

 

[Nikolai]

Clutch side coolant fitting done.

Some of my welds aren’t very good, curious to see how well it holds pressure when I test it and how many leaks I have.

Going to do the fittings on the chaincase side tomorrow.

 

[mysledblows]

Coming along. Love the project. You have a rear heat exchanger already? I’ve got one that I was going to throw in my turbo apex if I head cooling issues here in MN but never had an issue. Holler if you need one and I could grab some measurements and a pic or two

 

[kinger]

Which way will the coolant flow? Is there a block off plate in that little 45 degree tube? I love the idea of the coolant in the frame.

 

[Nikolai]

When thermostat is closed, coolant will flow out of bottom of T-stat into tube below motor and then up into water pump. (Orange)

When thermostat opens, coolant will flow out of T-stat into chaincase side 1” tube to rear cooler, down running board and into water pump. (Blue)

I do not have any block offs in the 45 tube. Leaving the water pump and t-stat to control flow and hoping it works fine.

 

[Nikolai]

Got the other 2 tubes tacked tonight. The one in the running board tube will go straight up into a 90 degree coolant fill fitting and then into left side of T-stat. Tube below motor will have hose going into bottom of T-stat.

I did some rough math estimates with my old stuff and I figured I saved at least 1 lb by running the coolant thru the framework.

Tight but it clears

 

[rallikuski]

I also love this project!
Awesome work and quality also.

 

[Dan Lance]

Need help on clutch offset, driving myself crazy, searched all last night and couldn’t find what I needed. I got my motor repositioned and am double checking the clutch offset before I make drivetrain plates.

Clutch offset from Yamaha is spec’d at 13.5-16.6mm. This is placing a straight edge on the backside of the primary clutch sheave and measuring to the backside of the secondary sheave. I’m using a piece of steel angle since it’s all I have right now. The secondary clutch has no spring in it but I have the sheaves closed.
View attachment 163701

Right now I have it set in the middle at 15mm but the secondary clutch is not centered on the primary clutch, it’s further in towards to the chassis.
View attachment 163702

Is this by design on purpose from Yamaha? I would think the correct offset would be whatever centers the secondary sheaves on the primary sheaves but if I do that then my offset would need to be 18mm.

What am I missing?

 

[Dan Lance]

As the secondary opens and the belt drops it moves to the outer side of the sled. By off setting the clutches at rest they can line the belt up better when in the normal operating range

 

[Nikolai]

Removed the motor and got the frame pulled from the jig. When I did the motor mount tabs I put a .002 shim on each side of the motor mount so the motor would come out easier. The width of the oem mounts is 1.925”, I made aluminum spacers that are 1.929” wide that I could bolt in while welding the tabs.

I need to
- finish weld rear suspension mounts
- finish weld motor mounts
- finish weld coolant tubes
- weld in a gusset on MAG side tubing
- cap ends of 1” tube below motor
- pressure test tubing for leaks

Then it can go back in the jig for drivetrain mounts and rear motor mounts.

 

[Nikolai]

Fused .063 caps on the ends on the 1” tube.

Pressure tested at 20 lbs.