Working on Rupp Roadster2

[OrangeAnimal]

HS40 engine runs I got the bike it has been restored but sitting for a bit. I got the carb dialed in now it runs smoothly doesn’t stall out etc but the engine burns oil mostly noticeable if you let it idle for a few seconds and then give it throttle. Some smoke comes out the breather and more out of the exhaust. Engine was and looks to have been rebuilt not too long ago. Not sure how good a job they did though. Where should I start besides verifying the oil level which also is strange cause the engine is on an angle. Do I check it with the engine sitting level by raising the front wheel of the bike or with the bike flat on both wheels (which seems like it would make more sense due to that’s the position the engine is in when riding).
That’s all I got for this evening hoping to get this bike running without it burning oil!

 

[Minimichael]

White or black smoke? I'd say you're probably onto something with the engine angle. Not sure what the recommended level is with angled mounts, but that info's gotta be out there. Start with a level lower than everything other than your oil dipper.

I'm guessing oil capacity on an angled flat head is around 15 to 20 percent more than standard.

 

[Triley41395]

HS40 engine runs I got the bike it has been restored but sitting for a bit. I got the carb dialed in now it runs smoothly doesn’t stall out etc but the engine burns oil mostly noticeable if you let it idle for a few seconds and then give it throttle. Some smoke comes out the breather and more out of the exhaust. Engine was and looks to have been rebuilt not too long ago. Not sure how good a job they did though. Where should I start besides verifying the oil level which also is strange cause the engine is on an angle. Do I check it with the engine sitting level by raising the front wheel of the bike or with the bike flat on both wheels (which seems like it would make more sense due to that’s the position the engine is in when riding).
That’s all I got for this evening hoping to get this bike running without it burning oil!

Do you have the original engine dipstick?
If the engine is not original to the bike you may need a different dipstick. If you didn't rebuild the engine yourself it might have just been cleaned up and repainted. Could be a ring or valve problem also. Post some pictures of the bike and engine. If you believe it's an oil level issue you might get this.

 

[OrangeAnimal]

I am going to check it later today and I will post a couple pics.
Blueish white smoke. It’s definitely oil.
I also am in agreement about they could have just cleaned it up and put it all back together. But they went through the trouble to vapor hone the case and head on it. And one head bolt is new albeit from the hardware store. Most likely a grade 5 bolt.

 

[Augiedoggie]

Not sure I’d ever hit the panic button for a puff of smoke from a small engine until several questions are answered. First should be oil quality and oil level. Lots of folks freak out when they run their engine after storage and don’t realize oil is diluted from fuel draining into crankcase. Unless oil is fresh, change it and refill to correct level. Few bucks for oil is peanuts. My other suggestion is not to worry about ANY smoke from engine that’s not fully warmed to operating temperature. These primitive engines are going to puff a bit when cold unless valve guide and piston clearances are factory fresh and tight. Crankcase is constantly aspirating and exhausting air and engine heat will vaporize moisture from air and force it out along with crankcase windage. Unless she smokes like a locomotive, I don’t fuss about it too much.

 

[pomfish]

Agree with Augiedoggie about oil change and then full warm up and run a good amount of time before wanting to tear engine down.
Rings may not have been seated after installation, etc.

I always say, New Oil's cheap, engines aren't

 

[OrangeAnimal]

Yes I did verify oil level correct it does have the dipstick as previously posted and it’s not much smoke at all. I told my buddy I wouldn’t worry about it. I rode it for about 20 mins the smoke doesn’t clear up but the oil is clean and fresh. Does not smell like gas is in it. I think it’s as good as it gets. Not sure how to post a video I may upload it to YouTube and link it here. Bike looks great and rides good too. Has good power considering the drive face on the sheave with the flyweights is a bit messed up and the belt alignment a tad off.

 

[manchester1]

If it hasn't been run very much after sitting, don't be afraid to change the oil again.

 

[sparkwizard]

Multigrade oils will make smoke. Try SAE 30 or 40.

 

[Triley41395]

How long have you had the bike. If just recently acquired maybe the previous owner put a little 2 stroke gas in by mistake.

 

[OrangeAnimal]

It belongs to a friend of mine who bought it a few months ago. He wanted me to get it running good make sure everything was good with it. It’s a really nice looking bike too. It’s not perfect in every way but it’s awfully close.
I am going to let him run it a bit after I fix the torque converter and do a couple other things. He wants to see about having the wheels re chromed. They have some light rust spots but really I would have left it be but that’s just me. The torque converter is a mess though. Had a lawnmower belt on it not even close to the right size and we decided to get the 30 series driver and install that and maybe if I can make it work the rear pulley as well.

 

[OrangeAnimal]

So after installing the tav30 driver pulley and realizing no real way to use the driven pulley on the jack shaft. I decided to install the inner driver sheave on the engine and use the tav30 outer driver so I can use a v shaped belt. This combination should work out I hope…. Waiting on the belt.

 

[OrangeAnimal]

Need some help. I got the rupp all back together but the cvt isn’t working well. I believe the belt is just too loose I have a 6061 on it but I am using a tav 30 driver. The only other belts I am seeing are a bit wider and shorter. Like the pl20507 belt

 

[bobco]

The Gates 6061 belt should be the correct length for your setup. The problem is those Chinese TAV30 drivers are made for a 3/4" wide belt. A 6061 is 5/8" wide. You need to turn about 1/8" off of the inner driver hub to make this engage at a reasonable RPM. The other issue is the springs in these engage at way too high RPMs. I think the best combo I found was the Comet pink spring at around 1600 RPMs.

 

[bobco]

Comet Torq-A-Verter Pink Garter Spring Set Of 2 011186A 011186A | eBay

 

[OrangeAnimal]

The Gates 6061 belt should be the correct length for your setup. The problem is those Chinese TAV30 drivers are made for a 3/4" wide belt. A 6061 is 5/8" wide. You need to turn about 1/8" off of the inner driver hub to make this engage at a reasonable RPM. The other issue is the springs in these engage at way too high RPMs. I think the best combo I found was the Comet pink spring at around 1600 RPMs.

I see what you mean and I had turned the od of the inner sheave down to fit the bushing from the 30 series to fit. But from what I am understand about the engagement speed I would need a stiffer spring in the drive pulley to make it not pull the belt in so quickly that the rpm’s climb so fast.

I am kinda wondering if I could take the spring from the other driven pulley and make that work out.
As far as the belt width I am using the 6061 belt and I have another belt on order. Should be in soon. I will mess with the combination till it goes.

 

[OrangeAnimal]

I see what you mean and I had turned the od of the inner sheave down to fit the bushing from the 30 series to fit. But from what I am understand about the engagement speed I would need a stiffer spring in the drive pulley to make it not pull the belt in so quickly that the rpm’s climb so fast.

I am kinda wondering if I could take the spring from the other driven pulley and make that work out.
As far as the belt width I am using the 6061 belt and I have another belt on order. Should be in soon. I will mess with the combination till it goes.

 

[OrangeAnimal]

The belt is so loose I can pinch it together in the middle. So I am pretty sure that’s a big part of the problem.

 

[willyb]

just tossing a couple old threads out here
https://oldminibikes.com/forum/index.php?threads/71-rupp-roadster-torque-converter-question.181671/
https://oldminibikes.com/forum/index.php?threads/rupp-torque-converter-replacement-options.161054/

 

[OrangeAnimal]

Yes I am looking at that also looked at trying to use the entire driven pulley from that set but it is going to stick out farther and just not look correct unless I could find someway to use the original cover by spacing it out. I am waiting on the belt that’s a bit shorter and then I may use the spring from the driven pulley in the kit. That stuff matched up would likely work. If it fits the original driver. This is a bike I am fixing up for a buddy of mine and it needs to look as original as possible keep as many oe parts as we can.