Bob Vehring
New member
Back in the day Micro Belmont used to make a sec. shaft that adapted SRV and V Max chain case to be able to use either a Pol or A/C secondary. They don't normally carry them anymore and are hard to find. We talked with them, they would make me one, somewhere around $160 or so bucks. I could use 3. This question comes up because while I talked with a friend that uses later model Phaser or SRX secondary, the cost of a helix and or spring for those is more then that. It still comes up that people are looking for these, wondering how much demand their really is.
Throttle Junkie35
New member
Hey bob. I see people looking for them all the time. I have two of those shafts myself. One uses the old style spline for the triple roller chain set up, the other uses the new spline for silent chain set up. Pm me if you want to use them as a pattern.
Bob Vehring
New member
My needs are for the SRV/ early V Max set up, not sure when things changed. Both use the same shaft, at least looking uo the part numbers. Good sec. tuning parts are either hard to find for the old stuff, or cost alot more for the newer Ph set up
If others are looking maybe a better price can be had. I have a spare shaft like this, they do again need one to work off of
If others are looking maybe a better price can be had. I have a spare shaft like this, they do again need one to work off of
a arctic cat sec will be the cheapest route to go as the helix are cheap and about every angle you could ever want, springs are also highly abundant.
Throttle Junkie35
New member
The triple roller set up is the same for vmax 540, srv, phazer, exciter up to 1990. You could convert your vmax and srv to the silent chain set up. You would need the jack shaft, drive axle and chain case off a 91-93 Exciter or 91-94 phazer.
I would think there would be a better market for the silent chain set up because the triple roller stuff is not as readily available like the silent gears and chains. Like I said, the shafts are identical with the exception of the gear spline. I wouldnt mind have one more of the never style. Your definitely right on as far as the Cat tuning stuff being easily found for peanuts compared to the yami stuff. Although I recently found the 49/39 helix is awesome on my exciter stock clutch.
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Bob Vehring
New member
My kid races USSA ovals, both sleds have Cat Sec. so we have trailer full of helix and springs I also have a Eltigre 6000 with a rev sec. as one of my toys. These never get raced seriously but have built engines. One SRV is a 550 with alot of work, The V Max is now a 618 big bore and interchangeable domes, and I have a SRV fan engine withich is 600 cc with Big reed cages welded on, welded up cyls with big porting etc. That engine I plan on putting into a stripped down 87 SRV for lake races. I understand that these are just 100 hp engines, won't be a player in 600 mod classes of today, I just like to see how fast I can make them. Stock old Yami sec just don't leave you with much choices so looking for the easiest way. Is the Yami silent chain stuff the same as older Cats used to use? I have gear selection from back when we drag raced years ago for those but I also have a selection of gears for the Yamaha triple row stuff here.
bottom cat gears fit the yamaha,chains are same 13 wide. top cat gears are smaller spline so they dont interchange.
I used to make conversion shafts by cutting the clutch end off a cat jackshaft, then cut the end off the yamaha, machine the cat end to a dowel pin about a inch long and radius the main cut to weld. machine yamaha shaft the opposite and bore the end to female of it leaving a slight press fit, .002-.003". Press them together and weld the seam in the fillet you put in the shaft ends, turn that on lathe.
i always cut them about 3 inchs from the pto side bearing support, seemed to hold up good. abused them pretty good on the grass with 7000rpm engagements,never broke one.
I used to make conversion shafts by cutting the clutch end off a cat jackshaft, then cut the end off the yamaha, machine the cat end to a dowel pin about a inch long and radius the main cut to weld. machine yamaha shaft the opposite and bore the end to female of it leaving a slight press fit, .002-.003". Press them together and weld the seam in the fillet you put in the shaft ends, turn that on lathe.
i always cut them about 3 inchs from the pto side bearing support, seemed to hold up good. abused them pretty good on the grass with 7000rpm engagements,never broke one.
Throttle Junkie35
New member
I was thinking of doing something similar. I thought about maybe spray welding the yami shaft then turning it down to fit the cat clutch and cut a key way. Seems like that would be less work.