1300 winter project

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bumper

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Soon the riding will be over here so I already am planning one of my winter projects. Building a 1300 for the max.

What I have so far is a 1987 venture case with the crank rods and pistons in it. I am going to replace the rods with vmax rods. I have a complete set vmax heads and a transmission from a 85 vmax. Of course second gear and the fork are fooked. I plan on upgrading the second gear and shifter drum. I will be running a big pipe Hindle completion plus pipe with the Morley jet kit and HD oiler. I want to keep my old enging in tack as much as possible. Its been a good runner with 17000 miles on it. I have about 85% of what I need to do the project and plan on working on it over the winter months. I have been reading as much as I can find on the 1300 build but I am sure I will have a few questions as the project moves along.

So next spring it should be a 1300 with 17 inch radial in the rear and radial up front also. I will notch the swing arm when I have the motor out. :eusa_dance:
 
Soon the riding will be over here so I already am planning one of my winter projects. Building a 1300 for the max.

What I have so far is a 1987 venture case with the crank rods and pistons in it. I am going to replace the rods with vmax rods. I have a complete set vmax heads and a transmission from a 85 vmax. Of course second gear and the fork are fooked. I plan on upgrading the second gear and shifter drum. I will be running a big pipe Hindle completion plus pipe with the Morley jet kit and HD oiler. I want to keep my old enging in tack as much as possible. Its been a good runner with 17000 miles on it. I have about 85% of what I need to do the project and plan on working on it over the winter months. I have been reading as much as I can find on the 1300 build but I am sure I will have a few questions as the project moves along.

So next spring it should be a 1300 with 17 inch radial in the rear and radial up front also. I will notch the swing arm when I have the motor out. :eusa_dance:

Sounds like it should scream, good call on the Vmax trans cause the gear ratios are better.. Sounds like you've got a good grip on what needs to be done, good luck bud! :)

sent from my HTC Rezound using tapatalk
 
Sounds like it should scream, good call on the Vmax trans cause the gear ratios are better.. Sounds like you've got a good grip on what needs to be done, good luck bud! :)

sent from my HTC Rezound using tapatalk

It depends on whether you want low end or top end speed.

The Ventures have a better transmission ratio for 1st gear than the VMax's. 2nd & 3rd are identical, while 4th & 5th favor the VMax for acceleration, but then lacking on top speed potential. 1st gear favoring the Venture is reasonable considering it was a much heavier bike and needed the higher ratio to give it reasonable takeoff. The VMax's had sufficient power for the weight to HP ratio. They also had a much higher revving motor capable of pushing the bike harder at in 4th & 5th.

Both charts assume a VMax final drive gearing.

Gary
 

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Soon the riding will be over here so I already am planning one of my winter projects. Building a 1300 for the max.

What I have so far is a 1987 venture case with the crank rods and pistons in it. I am going to replace the rods with vmax rods. I have a complete set vmax heads and a transmission from a 85 vmax. Of course second gear and the fork are fooked. I plan on upgrading the second gear and shifter drum. I will be running a big pipe Hindle completion plus pipe with the Morley jet kit and HD oiler. I want to keep my old enging in tack as much as possible. Its been a good runner with 17000 miles on it. I have about 85% of what I need to do the project and plan on working on it over the winter months. I have been reading as much as I can find on the 1300 build but I am sure I will have a few questions as the project moves along.

So next spring it should be a 1300 with 17 inch radial in the rear and radial up front also. I will notch the swing arm when I have the motor out. :eusa_dance:

Below is a short version of what it took to get a VMax configured 1300 block in my Venture.

The VMax heads only is a straight forward swap for the Venture heads. Only real change is the side plate that covers the cylinder pocket drain plug (sometimes called a freeze plug, which it isn't). This needs to be a VMax cover, the Venture plate is longer and covers part of head.

Carbs will need mains and one of the air jets changed with the VMax heads. Also needle valves should be changed to a VMax set. A set of carbs from an 86-93 Venture or a VMax are better due to being larger venturi size. You can not do this, but it will idle like crap and not develop power potential, trust me on this one. I used a set from aVenture 86-93 (87 in my case) set of carbs. These years had a 35mm bore set as compared to 34mm for 83-85.

The heads will probably need completely cleaned inside by sand blasting. This requires valves to be removed, which should be reseated by lapping. New valve guide seals also.

The VBoost is a whole nother can of worms. In addition to the VBoost intake assembly, a servo motor and mounting bracket is needed to operate manifold butterflies. It will not fit on the Venture in the same place it does on a VMax due to VMax's only have front coils mounted below TCI. Rear pair of coils are mounted on back end. This allows a space to mount servo motor. If you want servo motor to operate the way a VMax does, which is opening intake butterflies at 5,700 RPM's, a servo motor controller is needed. Or an Ignitech TCI can be used to replace stock TCI and it can control servo. Getting a VMax airbox in frame required removing the coils & installing COP's. This allowed the battery to be relocated on its side where the coils used to be.

A really tough part of getting VBoost intakes to fit is a clearance issue with the #1 carb and frame. The VBoost intakes are about 1 1/4" taller than stock. This creates an issue with #1 carb when carb rack is being installed, it just won't slide back far enough to drop into the rather stiff carb intake boots. I had to heat frame with torch at contact point and 'dimple' tube in some to get clearance to get carbs in and out. The stock air intake box will fit on the carbs without modification.

Next problem is the throttle cables interfere with frame in stock configuration and need modified with VBoost intake. And the choke cable needs modified.

The coolant line out of the Twinkie on the right side needs modified with VBoost.

There is little difference in the lower end except for doming on VMax pistons raises compression a little. There is also a slight difference in the oil galley, the VMax has an extra bearing oiler line on it. The piston doming difference can be compensated for by either milling block head deck about 0.040" or installing thinner Comitec (sp?) head gaskets.

As mentioned, the clutch should be upgraded. I didn't go Barnett route as it has limited upgrade possibilities. I used a diaphragm clutch from a Venture 86-93 style motor and doubled the diaphragm springs. This requires a clutch cover also from an 86-93 block. You really need a strong grip on left hand as this increases pull force on lever, but it don't slip if done right.

As I said, it depends one where you want to go with this. I would guesstimate $500 to $1000 to get it running decently. Carb rebuild alone, done right is at least $300 and up.


I also have an FJR final drive which is same gearing as a VMax. Bike has VMax rims on it. The rear wheel on a Venture is 16", by installing the 15" VMax wheel, I gained about 5% better low end gearing.

Gary
 
It depends on whether you want low end or top end speed.

The Ventures have a better transmission ratio for 1st gear than the VMax's. 2nd & 3rd are identical, while 4th & 5th favor the VMax for acceleration, but then lacking on top speed potential. 1st gear favoring the Venture is reasonable considering it was a much heavier bike and needed the higher ratio to give it reasonable takeoff. The VMax's had sufficient power for the weight to HP ratio. They also had a much higher revving motor capable of pushing the bike harder at in 4th & 5th.

Both charts assume a VMax final drive gearing.

Gary

Yea I was talking about drag racing because of the 4'th gear mainly, hell my engine runs pretty good and the engine just doesn't have the nuts to pull 5'th gear to redline as it is.. I was just talking strictly from a drag racers standpoint bud.
 
Gary, thanks for the chart, interesting reading. I ride my vmax around town and out a little. Not much open highway, I like the power and am looking for more. I have a dressed out Royal Star Standard that I use when I go on the road. One for speed and one for comfort. LOL.
What do you think is better? milling the head or the block ? Also is the u joint from a vmax any different (stronger) than the venture u joint ?
 
Gary, thanks for the chart, interesting reading. I ride my vmax around town and out a little. Not much open highway, I like the power and am looking for more. I have a dressed out Royal Star Standard that I use when I go on the road. One for speed and one for comfort. LOL.
What do you think is better? milling the head or the block ? Also is the u joint from a vmax any different (stronger) than the venture u joint ?

Milling the head does much less good than milling block., the head starts a very rapid conical shape and any milling gain is reduced by cutting into this conical shape. When milling block, machining reduces 100% of the diametrical area of the cylinder. See attached pictures for visual of this.

You can also put on thinner head gaskets. I don't know what the potential downside of thinner gaskets is, if any. Certainly cheaper than milling block, both mine have cost me about $180 to get milled. It takes a somewhat specialized mill to be able to cut into the v-shaped block. I think rear cylinders are the problem due to proximity of transmission portion of block.

Gary
 

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Note the 1300 and Vmax both have the same effective compression. The dome gives the vmax the extra needed to make up for the increase volume of the 1300's pistons.

Sean
 
Gary, thanks for the chart, interesting reading. I ride my vmax around town and out a little. Not much open highway, I like the power and am looking for more. I have a dressed out Royal Star Standard that I use when I go on the road. One for speed and one for comfort. LOL.
What do you think is better? milling the head or the block ? Also is the u joint from a vmax any different (stronger) than the venture u joint ?

U joints and yokes are the same.
 
good luck. place mod monkey traps everywhere . . . cause when you start this kind of work you may get of your purpose if the mod monkey reaches you..... i started a simple rebuild to my engine cause of a bearing but in the end i made a total restoration on the bike. 3 years passed and now i am reaching to finish my bike.
 
No light at the end of this tunnel...LOL I think I have a whole bunch of mod monkeys hanging around my garage and I thought those were mosquito bites.
 
No light at the end of this tunnel...LOL I think I have a whole bunch of mod monkeys hanging around my garage and I thought those were mosquito bites.

another 70 lbs box of monkeys is on their way.
 
Stock is about .032" and we can get cometics in about any thickness (though .027" is what we use in the MLS gasket).
 
So looking at only .005. Thought I could get away with not milling the block. I don't care if I have to burn premium. But looking at getting the compression up.
 
So looking at only .005. Thought I could get away with not milling the block. I don't care if I have to burn premium. But looking at getting the compression up.

I'd use the same gaskets Sean is recommending because I love mine but on such a small bore you could deck the block to its minimal tolerance and still not make much more compression. If you want to make more just bite the bullet and order pistons and get it up to 12:1, that'll actually make a difference. I know, I know, more monkeys and more money but you've already got it this far apart so now is the time ;)

sent from my HTC Rezound using tapatalk
 
I think we have taken as much as .040" off the stock block with stock gaskets and stock pistons/cams and still have it all clear. That will gain you an increase in compression. BUT, the intake and exhaust parts fit like shit (though they will fit).
 
I can get you anything you want. Not sure what I have on stock though.
 
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