Mount Angle for HT Bicycle Engine - 1st 4-stroke build ;-}

KCvale · Oct 22, 2011

Hi guys, I am new to the 4-stroke section here with my first 4-stroke build but I have a couple dozen 2-stroke builds under my belt so I'm not a rookie ;-}

I bought the Grubee HuaSheng motor with 4G T belt tranny kit ($375 delivered from gasbike).

How much of a backwards angle can I run this motor without a lube or carb problem?
With the springer fork and steep seat post angle I am a good 6° if not 10° back angle to conform to the back post mount.

As you can see I have little room on this Macargi Touch bike to go up.
Since I had to flip the motor mount plate around for the mount holes to line up and the front mounts sheer size the front mount can not be moved back any further without it covering the motor mount slots so I am in a bit of a pickle.

Thanks guys.

azbill · Oct 22, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

I have always been advised to mount as level as possible,,,
these engines are splash lubricated, so they need it that way AFAIK

bandito · Oct 22, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

Yea if its angled it could cause problems especially going up or down a hill.

scotto- · Oct 23, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

That little of angle won't make much difference, trust me. As for the mounting plate not clearing the mounting blocks......drill and tap holes into the blocks. Don't be afraid to experiment a bit, they're tough little engines.

dnut

KCvale · Oct 26, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

To get the motor level it had to go forward but the front bracket hit the vertical motor mount bolts preventing it so I had to break out the grinder.

Then with a new hole in the chain guard mount I was able to lower it an inch down closer to the pedal chain so the motor could go down more as well and she fits with just barley enough room to work that lame top mount choke lever.

Isn't there supposed to be a different choke option for these things?

Anyway, the HT 4-stroke can fit in a 26" Macargi Touch bike with some minimal mods, it just looks like a motor with wheels ;-}

azbill · Oct 26, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

I have only ever used to choke to get gas to the carb to start the engine
(no primer bulb)
full choke,,,1-2 pulls,,,starts right up then off goes the choke

if the engine is warm, I rarely need to prime it

flex man · Oct 26, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

Also if you get rid of that muffler and put on a flex pipe or any kind of header agk has a few good ones . it will give you more power and more room. If your not sure if there would be a room advantage try taking off your muffler
and put the motor back in the frame and see.it might help. also the stock air cleaner is to tall get one from sbp or agk that will also give you a little bit but all you need is a little..Flex..

KCvale · Oct 26, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

Thanks for the tips guys.
I won't have a 'gas to the carb' problem, the tank is going on the top bar.
As for room the motor has next to no front/rear movement but I do still have some lateral movement to get the chain aligned, speaking of which, what the heck is with that 50T sprocket!?

The center hole AND the bolt pattern are smaller than a stock 2-stroke kits. Why?

What a pain in the ass to mount the sprocket to the wheel.
What really amazed me is the frigg'n manual even says you may need to use a machine punch or Dremel tool to make the hole bigger and their 'quick way' is to do that and then put the sprocket right up against the spokes cupped dull side teeth out!

That's OK, I got it to 'fit right' cupped in with a rag on each side of the spokes.
Speaking of the 'rag joints', if there was any doubt they use the sidewalls of used tires to punch the joints out of, this should lay that doubt to rest.

When you can read the tire sidewall text it's game over ;-}

The_Aleman · Oct 27, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

To answer your original question, the engine can be mounted up to 20 degrees off level according the the GXH50 manual.

KCvale · Oct 28, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

The_Aleman said:
To answer your original question, the engine can be mounted up to 20 degrees off level according the the GXH50 manual.

Thanks Aleman! I didn't think to look in the manual of the motor HT cloned, good thinking ;-}

20° is a lot of leeway for future reference but I didn't need it, I got the motor dead level.

The is done all but the tranny as I want to start and run the motor for awhile before I put it on and it was too funny yesterday...
Here I am ready to try it out and an MB friend was over and he wanted to know what pre-mix gas to put in it, 25:1 or 32:1 and said neither, just plain gas.
I poured it in and was about to pull the rope and he said "well, what lubricates the motor?"

DUHHHH... I hadn't put in any crankcase motor oil yet!
That sure saved my butt, but to my chagrin I could not find so much as a single drop of motor oil here so it's off to the auto parts store this morning.

Any suggestions on a motor oil to use?

The_Aleman · Oct 28, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

Straight HD30 is what the manual calls for, but you can use just about any motor oil you want. I recommend 15W40 for all-around use. It's a heavy duty oil.

I used HD30 in mine for the first 2 oil changes - a few hundred miles, then switched to a full synthetic.
Now I run 20W50 for summer, 10W30 for winter, both full synthetic.

GearNut · Oct 28, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

Interlube International, Manufacturers of premium Opti oils, Opti-2 and Opti-4
______________________________

scotto- · Oct 29, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

Break-in with this: Premium4 - $7.95 : Maxima Racing USA, - Overkill

then run this: SynBlend4 - $10.50 : Maxima Racing USA, - Overkill

Then after 30hrs. I use full synthetic which is this: Ultra4 - $16.50 : Maxima Racing USA, - Overkill

Some of the best oils known to man, but use whatever you like.

dnut

KCvale · Oct 31, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

Thanks.
So whats up with the woodruff key? The damn thing sheared off in 1/4 mile!
No frigg'n set screws in it, no room to drill and tap a couple in, just a lame nut and that key to hold it on? What a JOKE!

Anyone know a source for a better drive gear or at least a titanium woodruff?

It did turn out nice though and ran great for that 1/4 mile.

It stops good too. Independent front and rear side pull brakes as well as the rear coaster brake.
Overkill? Not in my book. Riding with just a coaster brake is a trip to the emergency room just waiting to happen and if I'm going to put on one brake, why not two right?

GearNut · Oct 31, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

KC, How well do those wide cranks fit? Do they clear the engine and trans with plenty of room to spare or do they just clear with minimal clearance?
I ask because I will need to get some for my Pointy Beach and I want them to clear with minimal clearance. I do not wish to pedal bowlegged ya know?

The_Aleman · Oct 31, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

hey KCvale, exactly which key sheared on you? Clutch/Primary? Output?

I've never sheared a key on my 4G, but the key they give you for the clutch is junk. I made a new one before I put any miles on the bike.

MotoMagz · Oct 31, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

GearNut said:
KC, How well do those wide cranks fit? Do they clear the engine and trans with plenty of room to spare or do they just clear with minimal clearance?
I ask because I will need to get some for my Pointy Beach and I want them to clear with minimal clearance. I do not wish to pedal bowlegged ya know?

If you want the cranks to barely clear go with the SBP cranks for the 4 stroke shift kit.It is as close as you can get....if your engine is on a slight angle the cranks will rub.

The_Aleman · Oct 31, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

To add to MotoMagz post, the spindle you'd want to use is the 206MM. That's the one included with a 4-stroke shift kit and the widest SBP offers.

Also, not sure what you mean by rubbing if the engine is at an angle. My engine tilts back at a 6 degree angle and the cranks clear the 4G cover.
Front or rear angle won't matter, left or right angle would. But then, who would put their engine at a left or right angle?

KCvale · Nov 7, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

It was the output sprocket gear key and it was my fault.
I messed up my back pretty good a couple weeks back (it's still really messed up, went to Urgent care twice already) so I let a MB friend mount the tranny and I didn't check his work.

He left out the spacer between the back of the gear and tranny so the nut couldn't tighten up against the gear on the other side.
Since that spacer and new key were in it has run great.

The kit cranks are short and really bowed, I can fit a tennis ball between the cranks and the motor at the closest point on either side and you do ride bow legged. Surprising considering how low I got the motor to sit.
If I would have had more time with it I would have tried standard cranks as I think they would have worked better.

I see a lot of room for improvement with these 4 banger kits, but that is part of the reason I enjoy building these things, making things better is like inventing to me and I live to invent.

Next up is 4 a stroke shifter and some performance mods.

scotto- · Nov 7, 2011

Re: Mount Angle for HT - 1st 4-stroke build ;-}

I run the stock cranks on an SBP 206mm cartidge BB spindle for minmal clearance on all but my 212cc as it is 14" wide and needs those dog legged stubby cranks that come with a kit....lol

dnut

KCvale said:
It was the output sprocket gear key and it was my fault.
I messed up my back pretty good a couple weeks back (it's still really messed up, went to Urgent care twice already) so I let a MB friend mount the tranny and I didn't check his work.

He left out the spacer between the back of the gear and tranny so the nut couldn't tighten up against the gear on the other side.
Since that spacer and new key were in it has run great.

The kit cranks are short and really bowed, I can fit a tennis ball between the cranks and the motor at the closest point on either side and you do ride bow legged. Surprising considering how low I got the motor to sit.
If I would have had more time with it I would have tried standard cranks as I think they would have worked better.

I see a lot of room for improvement with these 4 banger kits, but that is part of the reason I enjoy building these things, making things better is like inventing to me and I live to invent.

Next up is 4 a stroke shifter and some performance mods.

Mount Angle for HT Bicycle Engine - 1st 4-stroke build ;-}

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