YD100 Top Speed

[ImpulseRocket]

I just want to have the satisfaction of working out the issues of building something that was never meant to go together, but makes an a$$ load of power

If you want to do that, go big or go home and do what I plan to eventually do. Buy a cdh 110 bottom end and build a 56mm MS660 based saw engine and have a 98.5cc beastie.

 

[GW's Motorized]

If you want to do that, go big or go home and do what I plan to eventually do. Buy a cdh 110 bottom end and build a 56mm MS660 based saw engine and have a 98.5cc beastie.

The ms 460 is enough for me, but I'll look into the 660. If it isn't too expensive I'll probably do that.

 

[Whitewill1412]

I just want to have the satisfaction of working out the issues of building something that was never meant to go together, but makes an a$$ load of power

I agree. It's more fun to build something than buy something

 

[LewieBike]

It would be interesting to see if a Chinese company could build bike engine bottom ends made for direct mating up with the cylinders from Dolmar cutoff 66cc saws or the cylinder of Jonsered's 2152, (which I own one and it's just a really nice saw with a really wide torque curve...) The Dolmars are famous for having exceptional low end pull. It's why Wacker and Makita use their engines on their steel cutoff saws.

 

[GW's Motorized]

The

It would be interesting to see if a Chinese company could build bike engine bottom ends made for direct mating up with the cylinders from Dolmar cutoff 66cc saws or the cylinder of Jonsered's 2152, (which I own one and it's just a really nice saw with a really wide torque curve...) The Dolmars are famous for having exceptional low end pull. It's why Wacker and Makita use their engines on their steel cutoff saws.

Saw engines make good torque with the right gearing

 

[LewieBike]

The

Saw engines make good torque with the right gearing

Yeah but nominally most of these quality saws all have tended since Husky's XL series of being rated to run best at high rpm They fall off the torque curve below about 4~5 thousand rpm Since most people run bike engines as single speeds being able to dig in at 2.5K or more and walk up the RPM scale while pulling a fair load without a flat spot. My Jonsered uses the same cylinder as the Husqvarna but the discussion on saw forums are that Jonsereds are a little better at pulling through heavy loading at lower RPM's. I'm not sure if that is due to port timing or maybe cutouts in the crank flyweights.

I've owned a few SAAB 2 stroke cars and the "standard" crank with the counterweight cutouts tended to pull from lower RPM better compared to the "stuffed" full circle cranked GT850 or Monte Carlo triple carbed sports engines. These sports heads have a smaller squish dome, and their exhaust collectors have another pipe to the rear muffler. It means that while the stock engine, which makes about 40 very tractable horsepower, the SAAB Sport engines makes 65 hp, but has a very weak just above idle torque curve until you get to about 3.5K. Very much like the way Kawasaki's triple H2 comes on compared to the Suzuki GT550.

 

[cdeuce1988]

Appreciate the info. I've had to ride my bike everywhere for the past 7 years so I've adjusted well to it lol.
One thing I never did hear about was helmet mirrors... had to look it up. I would never wear one because I feel goofy enough wearing a helmet , but I did buy one and do wear it with the gas motor... I did put mirrors on the bike as well but I'm probably going to take them off since they don't do anything... the bike vibrates too much to see anything out of them (plus even with the bike not on, they're too small to be worthwhile).

You need to get you 1 good mirror. The left side mirrors work well in my opinion..

 

[Majicfingers@1]

So my YD100, still breaking in, fastest I got it so far has been just under 35mph (today actually)... I was wondering how fast other YD100 owners have got their motors and what mods have been done to achieve that speed. I really want to be able to go 55-60 (Iol I know... I'm prolly dreaming) not to use on the regular at that speed but just to have it in my back pocket... It would be nice to at least go 40-45 to be around the speed limit and not constantly get passed

I read on here the other day to wait until the engine was fully broken in and then add mods one at a time and I really wish I saw that sooner... if for no other reason than to see what performance they truly added, if any...(who knows, I might be going faster with stock parts)

I think this coming weekend, I'm going to throw the BoFeng back on there for giggles and see if there's any performance difference between the HP.... (which I think I finally got in tune... fingers crossed... today it worked like a charm...)

Also , as per forum advice, I switched to conventional oil for break in purposes... I def. feel a difference between conventional valvoline and fully synthetic stabil... feels like it takes a little longer to start (or that could be because of how I tuned the carb... as I did them both yesterday)

Anyhow, as usual I appreciate you all. You guys are awesome. Can't wait to read the comments. I'm glad I found this forum.

I run an expansion chamber on mine and a short intake and fuel mix is 32:1 Mine runs 45 to 50 mph. Gets sorta scary on bicycle tires of which I run heavy-duty ones with kenda koss.

 

[ImpulseRocket]

I run an expansion chamber on mine and a short intake and fuel mix is 32:1 Mine runs 45 to 50 mph. Gets sorta scary on bicycle tires of which I run heavy-duty ones with kenda koss.

if you can get a legit 45mph out of a YD100 without port work I would love to know who you got the cylinder from. I have never seen a standard YD cylinder that had port timing and duration numbers that could manage that kind of power, even with a good expansion chamber.

 

[cdeuce1988]

So my YD100, still breaking in, fastest I got it so far has been just under 35mph (today actually)... I was wondering how fast other YD100 owners have got their motors and what mods have been done to achieve that speed. I really want to be able to go 55-60 (Iol I know... I'm prolly dreaming) not to use on the regular at that speed but just to have it in my back pocket... It would be nice to at least go 40-45 to be around the speed limit and not constantly get passed

I read on here the other day to wait until the engine was fully broken in and then add mods one at a time and I really wish I saw that sooner... if for no other reason than to see what performance they truly added, if any...(who knows, I might be going faster with stock parts)

I think this coming weekend, I'm going to throw the BoFeng back on there for giggles and see if there's any performance difference between the HP.... (which I think I finally got in tune... fingers crossed... today it worked like a charm...)

Also , as per forum advice, I switched to conventional oil for break in purposes... I def. feel a difference between conventional valvoline and fully synthetic stabil... feels like it takes a little longer to start (or that could be because of how I tuned the carb... as I did them both yesterday)

Anyhow, as usual I appreciate you all. You guys are awesome. Can't wait to read the comments. I'm glad I found this forum.

So I got my yd100 up to 43mph but it wasn't that easy. . So I got a g2 Reed , windowed and skirted piston, 3rd transfer , 28 tooth sprocket in the rear ,11 tooth rdm drive sprocket in the front, mz65 clone exhaust with a modified ( baffle completely removed from the inside. I had to cut the muffler at the top where it opens up, where the battle starts when yank the entire baffle out then weld it back together including the cap on the bottom because once baffle is removed there's no way to screw the cap on at the bottom. You gotta weld it. ) Stock Muffler welded onto it as a silencer.