Is the Mikuni 42HSR Worth It?

[davej]

unless you have internal engine work done to the bike a HSR45 is way to big for the bike. If you want a HSR carb stick with a HSR42.

[Bobbin-Martin]

unless you have internal engine work done to the bike a HSR45 is way to big for the bike. If you want a HSR carb stick with a HSR42.

Thanks for the info. No internal work done to it. When I was researching and thinking of doing it, Patrick Racing no longer made the cam kits for the 1600. Ive been spitballing the idea of a 1900 swap from a roadliner, but don't exactly know if its plug and play.

[davej]

no where near plug and play

[Bobbin-Martin]

no where near plug and play

Boooo. If you don't mind my asking, what makes it not a plug and play swap? I know I've heard some things about the transmission holes being different diameters, but what else is there. Is it relocating the mounts? Is the cradle from the 1600 not big or strong enough for a possible difference in weight and height?

[roadiemort]

If you got to ask the question then the job isn't for you lol.

[Bobbin-Martin]

Im new to bikes. Only had mine for about a year. Im actually a mechanic by trade. I just want to know if its possible, before I pull the trigger on a used engine from ebay, or if its gonna require so much fabrication, that it would just be better to buy a roadliner.

[Shores]

Im new to bikes. Only had mine for about a year. Im actually a mechanic by trade. I just want to know if its possible, before I pull the trigger on a used engine from ebay, or if its gonna require so much fabrication, that it would just be better to buy a roadliner.

Most mechanics know that a 427 V8 isn't a direct swap for a 289 V8. If you're needing a new engine for your road star, just buy a new used engine. If you want the horsepower from a stratoliner then just buy a stratoliner or a roadliner. Size is different, mounting is different, exhaust is different, wiring harness is different, etc.

[Bobbin-Martin]

Well on cars and trucks, something like the proven LS platform can be swapped into just about anything from a Toyota, Nissan, or even a BMW, granted you relocate motor mounts, use an adapter for bell housings, and if your running fuel injection, have a jumper harness or stand alone management for the ECU. If you go carburated and run a manual, well all you really need to run would be the wiring for lights and other amenities. On a bike thats carburated, and doesn't have many electrical components to the motor or transmission, other than the TPS and fuel pump, I can't see the harness being that different, especially considering yamaha likes to reuse alot of parts from the bin and such. I just want to know if its been done before, and if so, what were the hurdles to overcome. With the lack of information im getting though, really starting to think its best to just put money aside for a strat, or just make my XV1600AS look nice and pretty, and buy something like a naked bike to scratch that itch for power I got.

[Bobbin-Martin]

Most mechanics know that a 427 V8 isn't a direct swap for a 289 V8. If you're needing a new engine for your road star, just buy a new used engine. If you want the horsepower from a stratoliner then just buy a stratoliner or a roadliner. Size is different, mounting is different, exhaust is different, wiring harness is different, etc.

There's nothing wrong with my motor. Im just a gearhead, hot rodder, and a bit of a speed freak, than can never leave well enough alone. Just wondering if by the time I put a 2-1 exhaust, BAK, and a 42 mikuni, if the gains will be noticeable enough to scratch that itch or if a bigger motor that makes close to 100 hp in its stock configuration would be a better option and have more of a tuning potential. I like making things that have no business being fast, well just that, fast, or faster at the very least

[davej]

I guess you can put anything into anything but it is not a direct swap plug&Play. If you want power get a 1700 engine and do a 110 Big bore. That is basically a Plug&Play. I have a 110 Big Bore and it will run in front of just about any bike in this class of bike that is on the road. There is not much in the cruiser class that will touch it.

[Bobbin-Martin]

I guess you can put anything into anything but it is not a direct swap plug&Play. If you want power get a 1700 engine and do a 110 Big bore. That is basically a Plug&Play. I have a 110 Big Bore and it will run in front of just about any bike in this class of bike that is on the road. There is not much in the cruiser class that will touch it.

Awesome. Any kits that you would recommend for the big bore or is it just Patrick Racing that deals with our bikes?

[Brad_G]

Boooo. If you don't mind my asking, what makes it not a plug and play swap? I know I've heard some things about the transmission holes being different diameters, but what else is there. Is it relocating the mounts? Is the cradle from the 1600 not big or strong enough for a possible difference in weight and height?

If you’re talking about bigger diameter bolts I’m wondering if you’re referring to a Warrior and not a’liner series. Duke recently did something along these lines.

The ‘liners are all dual throttle body fuel injection. So lots of components and wiring will be different. Best bet would be to buy that model if you want one. Or as mentioned a big bore kit for a Road Star if you can source one.

[Bobbin-Martin]

If you’re talking about bigger diameter bolts I’m wondering if you’re referring to a Warrior and not a’liner series. Duke recently did something along these lines.

The ‘liners are all dual throttle body fuel injection. So lots of components and wiring will be different. Best bet would be to buy that model if you want one. Or as mentioned a big bore kit for a Road Star if you can source one.

Possibly, I remember seeing the post on here, so that might be what I saw. So the roadliners and stratoliners are Fuel injected? Gotcha. Thought it was just the 1900 in the raider that was fuel injected and that the roadliner and strat were carburated. So thats why an earlier post mentioned the harness, makes sense since you would need a harness that could run all the cam position sensors for timing, fuel pressure, etc. So Duke is putting a 1900 in a Road Warrior? This is my 1st bike, so I'm kinda attached to it. I will get more bikes, just this one will always be my 1st and as such, I was hoping I could tweak it just a bit to give the ole girl some more grunt and pep in her step. I also see what you mean by sourcing it. Having a helluva time finding certain things for this bike. Btw sorry for all the questions, I get carried away when it comes to mechanical things

[Shores]

I don't believe Duke was putting a 1900 in a warrior, I believe he was using warrior components on a roadstar.

[Bobbin-Martin]

I see. Thanks. I'll ask Duke what exactly he was goin for, cause I thought he was doin a 1900 swap and I was like "ok, so there's a possibility this will work lol"

[davej]

Patrick racing is the only one for Big Bore. The kit PCS sells comes from Patrick Racing

[Bobbin-Martin]

Understood. So what kind of numbers did you see if you ever got to tune it on a dyno and what support mods did you have to do, to get the most out of your big bore. Did you end up using the hsr45, dyna3000, and all those other goodies?

[Duke]

From what I understand is the 1900 engine is a taller engine due to the longer stroke crank. The1900 engine case is different then the RS and Warrior case. Trying to put a 1900 engine into a RS frame would take a lot of fabrication and I think it wouldn't be worth all of the headaches.
The Warrior engine case is basically the same as the RS and the only thing different is the 3 bolts on the left side that mounts the transfer case to the engine are larger on the Warrior. The Warrior uses M10 bolts and the RS uses M8 bolts. EZ to do.
Be aware that the transmissions have a little gear ratio differences. Not a big deal, just need to use one or the other transmissions in the cases.

I'd would like to try to use the Warrior heads on the Road Star, due to the better breathing capabilities of the Warrior, but it would take making a custom intake manifold and custom exhaust pipes. Maybe one day, I'll try?

[Bobbin-Martin]

From what I understand is the 1900 engine is a taller engine due to the longer stroke crank. The1900 engine case is different then the RS and Warrior case. Trying to put a 1900 engine into a RS frame would take a lot of fabrication and I think it wouldn't be worth all of the headaches.
The Warrior engine case is basically the same as the RS and the only thing different is the 3 bolts on the left side that mounts the transfer case to the engine are larger on the Warrior. The Warrior uses M10 bolts and the RS uses M8 bolts. EZ to do.
Be aware that the transmissions have a little gear ratio differences. Not a big deal, just need to use one or the other transmissions in the cases.

I'd would like to try to use the Warrior heads on the Road Star, due to the better breathing capabilities of the Warrior, but it would take making a custom intake manifold and custom exhaust pipes. Maybe one day, I'll try?

Thank you kindly for the information Duke. I think fabricating an exhaust would be the easier of the 2 endeavors. I think the intake manifold would be the bigger issue. Im quite honestly suprised that no one ever really made a metal one to alleviate the cracking of the plastic ones, and that everyone just ports the plastic.

[roadiemort]

Thank you kindly for the information Duke. I think fabricating an exhaust would be the easier of the 2 endeavors. I think the intake manifold would be the bigger issue. Im quite honestly suprised that no one ever really made a metal one to alleviate the cracking of the plastic ones, and that everyone just ports the plastic.

Probably because the stock cast aluminum with rubber molded to the aluminum are more forgiving for everyday use not just drag racing.

[Duke]

The problem with a rigid intake manifold is expansion and contraction of the engine top end. As the engine warms up, the cylinders grow causing the intake mating surfaces to change, and is why Yamaha uses rubber manifolds. The aluminum manifolds that were being sold years ago were having sealing problems. If done correctly, they will work.
I still use the aluminum manifolds, but use a rubber gasket and sealant between the flanges. So far, I haven't had any problems.

[Bobbin-Martin]

Gotcha. So was yamaha using those silicone beads?

[davej]

Bobbin-Martin check my profile by clicking on my screen name then click on "about" it has all the details of my bike.

[Bobbin-Martin]

Will do. Thanks Dave

[Wayne Bradford]

I think these bikes run pretty good for what they are. I bought a 1700 last month (my second) and it has a Mikuni 42, K&N, 2into1 and i think it must have the Barnett clutch mod because the clutch has the hardest pull of any bike I have owned and can't be stock. (it's not too hard for me to pull though)
The needle and seat was dripping when I first got it so I put a new OEM N&S in it. While i was there I noticed that it has a 185 main jet which I think might be to big, I will try a 175 in it soon.
If speed is what you are after this bike is not it compared to many others like the Busa, ZX14 and Concours I used to own. I personally like the torque of a big twin, however IU don't care for the vibration they give.

[Ahodge75]

I did the 110 big bore kit on mine with Duke last year. Now mine isn’t as modified as Davej’s but there is a noticeable difference from stock. I’m Happy I did it for sure. Like Dave said for its class with the 110 big bore not much touches it. If you are looking for some extra to scratch the itch it’ll do it but it’s not going to be that high revving sports beast, it’s going to be a torque monster that’s a lot of fun…..just my 2 cents.