Found one for $1000 cheaper than the last one.
http://www.kijiji.ca/v-sport-bikes/...ke/1104782863?enableSearchNavigationFlag=true
|
|
|
Rebuilding a 2 stroke?
- Thread starter unL33T
- Start date
Found one for $1000 cheaper than the last one.
http://www.kijiji.ca/v-sport-bikes/...ke/1104782863?enableSearchNavigationFlag=true
Hmm I got gas this morning and made sure to pick the 91. Just entering the information off the receipt into Fuelly now and see that they charged me for regular. Now I wonder if they just miss billed me or somehow the pump decided to give me regular instead. I've only ever had the opposite happen once before (selected regular and the pump gave me premium, and charged it as such).
How much damage am I going to do with a tank of 87 in it? Guess I should stop somewhere and grab some octane booster.
How much damage am I going to do with a tank of 87 in it? Guess I should stop somewhere and grab some octane booster.
Anyone have any thoughts on using Bombardier XPS full synthetic in my bike? It's group V ester based just like Motul 710 and Redline oil but costs 1/4 as much as Redline and is about 1/2-2/3 the price of the Motul. Says it's for Rotax engines but I've always read that you shouldn't use snow mobile oil in a motorcycle. Bombardier told me it should be good in the bike but they can't say for sure. Figured if I can save a few bucks on a high quality group V ester oil, why not?
In the mean time I stocked up on the Motul because I can't get Amsoil as easily any more and the place I bought it said once they have to order more stock the price is going way up because our dollar is so bad.
In the mean time I stocked up on the Motul because I can't get Amsoil as easily any more and the place I bought it said once they have to order more stock the price is going way up because our dollar is so bad.
Last edited:
boyoboy
Well-known member
did you use the advertised compression ratio in your "equation"? or actually do the calculation from port closing ?
the bike was previously running on pump gas w/o detonation, still wondering why you would drop CR. did you correct the squish?
what method(s) did you use to lower CR?
Last edited:
boyoboy
Well-known member
two stroke racers love the motul. why mess with success.
Because it's expensive. $15/L at a special rate and it's going up. Redline is loved, too, but that's $12/470 mL (and near impossible to find). The Bombardier stuff is like $10/L.
Getting the cylinder replated. After many emails to CVTech AAB in Quebec, with no response, I called them and they told me to just ship it to them with a note about what I want (replating/repair, piston, and gasket kit). Didn't hear anything for about a month. Then I get a call from someone that barely speaks English asking for my credit card number. I was out so I call them back. Again they want my credit card number. They had no idea I wanted a piston and gasket kit even though I mentioned it in my phone call and in the note included in the package. Despite the fact that they gave me a price already for the piston it takes the guy about 7 minutes to find one in his system this time and it's special order out of the US and would not be special sized to fit the cylinder in any way. Oh, and they can't get a gasket kit. In the end I told them to just send me the repaired cylinder and I will measure it and order a matching piston and gasket kit out of the US myself. Overall I'm not the happiest with their customer service (could be worse though) but hopefully they did good work.
Last edited:
boyoboy
Well-known member
the RS125 thread lives again! there is sandy at Pro 6? still? (the sandy delboy referred to i believe) is known to be a good 2 stroke guru) may be a guy you want looking at this.
there is also gord bush who is known to have put together some fast rz350's in the day (and also built honda canada race engines) he may or may not have interest in your RS.
both these guys are in etobicoke
edit: there is in my humble opinion - a case to be made for not building a 2 stroke with TOO much compression. if it were my engine i wouldn't want to have more than 160 psi, nor less than 140 psi - and 140 psi may likely be better for your street bike on premium pump gas.
however, most 2 stroke tuners don't go by cyl psi, but rather by actual compression numbers calculated from port closing. this is more accurate and generally accepted by tuners as the "proper" method for engine builds. these numbers can be as high as 8.0 to 1 for race engines (or higher). tuned street engines are generally around 7 to 1, (give or take depending on engine). Advertised compression ratios are just that -advertising- and really don't have any value.
long story short, get one pro to do everything in shop. start to finish. and be sure he understands your bike will be used for street riding on pump gas. you want a 2 stroke tuner, not a mechanic, for putting your RS125 engine together- a rare specialist who will look at ALL factors when putting together your rare and highly tuned RS125 engine. this will mean looking at and measuring everything from piston, rings, cylinder, gasket thickness(s) and optimizing squish clearance, to final machining with a calculated compression ratio. please don't just bolt it together and hope for the best. when done properly, it should, and will, run better than new.
can't wait for delboy to chime in here, 2 stroke bikes are his "thing" and he has lived with an assortment of the critters. delboy?
there is also gord bush who is known to have put together some fast rz350's in the day (and also built honda canada race engines) he may or may not have interest in your RS.
both these guys are in etobicoke
edit: there is in my humble opinion - a case to be made for not building a 2 stroke with TOO much compression. if it were my engine i wouldn't want to have more than 160 psi, nor less than 140 psi - and 140 psi may likely be better for your street bike on premium pump gas.
however, most 2 stroke tuners don't go by cyl psi, but rather by actual compression numbers calculated from port closing. this is more accurate and generally accepted by tuners as the "proper" method for engine builds. these numbers can be as high as 8.0 to 1 for race engines (or higher). tuned street engines are generally around 7 to 1, (give or take depending on engine). Advertised compression ratios are just that -advertising- and really don't have any value.
long story short, get one pro to do everything in shop. start to finish. and be sure he understands your bike will be used for street riding on pump gas. you want a 2 stroke tuner, not a mechanic, for putting your RS125 engine together- a rare specialist who will look at ALL factors when putting together your rare and highly tuned RS125 engine. this will mean looking at and measuring everything from piston, rings, cylinder, gasket thickness(s) and optimizing squish clearance, to final machining with a calculated compression ratio. please don't just bolt it together and hope for the best. when done properly, it should, and will, run better than new.
can't wait for delboy to chime in here, 2 stroke bikes are his "thing" and he has lived with an assortment of the critters. delboy?
Last edited:
boyoboy
Well-known member
something wrong here, they would want the piston BEFORE they do the cylinder plating/final honing. perhaps they went with OEM specs and didn't do final honing? not sure how this would work.
Last edited:
No idea. I just went with them because they were recommended. May not have been worth it, either, as the replating was close to $400 CDN on it's own and a new cylinder kit with the piston and gasket kit is like $500 USD.
Bike is still running great after the repair. Dunno if the performance is much lower since I was only getting 90 PSI last I checked it but it seems to run fine. It'll exceed 150 kph indicated still. Just had the cylinder done as a spare.
boyoboy
Well-known member
good to hear the RS is on the road.
Thanks. It has been since last season. Took a couple months to get all the parts and have the repair done, from what I recall.
Got the replated cylinder in the mail today:
Regular type calipers won't work. You need, ideally, a bore gauge... I don't have a bore gauge either, so I use a telescoping gauge kit.
You need to measure the bore one third ,then two thirds from the top, measuring twice at 90 degree angles at each step.
Do you have a piston?
What you're REALLY interested in is the piston to bore clearance.
Put the piston in the bore about half way down and ram feeler gauges down in there beside the piston. The biggest one (decided by two) is your piston to wall clearance. (Move the piston up and down to be sure it is the same everywhere).
If you want it is very simple to get that thing some more compression. Bring it up and we'll swap the base gasket... and I could measure that bore for you.
You need to measure the bore one third ,then two thirds from the top, measuring twice at 90 degree angles at each step.
Do you have a piston?
What you're REALLY interested in is the piston to bore clearance.
Put the piston in the bore about half way down and ram feeler gauges down in there beside the piston. The biggest one (decided by two) is your piston to wall clearance. (Move the piston up and down to be sure it is the same everywhere).
If you want it is very simple to get that thing some more compression. Bring it up and we'll swap the base gasket... and I could measure that bore for you.
|
|
|
|
|