First build - the journey begins

[Rudz]

I bought a 19“ mtb with front suspension from bikes direct, I plan on building a decent mtb that happens to have an 80cc motor.

http://www.bikesdirect.com/products/dawes/hay1000xi.htm

Disc brakes, lock out forks and it was cheap.

Got it, put it together, rode it. Now I'm waiting on my motor.


Parts ordered

California Motorbike wildcat engine kit
Frame mount
Dual pull lever
Sram thumb shifter sans brake levers
New cables
CatEye 7 computer
Origin 8 bat wing bar
Kings top hat disc adapter
Spring chain tensioner with sprocket

I already have a cygolite hotshot, helmet, mtb pedals and plenty of cycling gear

Plan on ordering

Maxxis tapeworm 2.5 tires with downhill tubes
Arrow torque pipe
Extended manifold
Dellorto SHA 14.12 carb
Brooks b67 spring saddle
Jaguar cdi
Avid bb7 brakes
bicycle designer 255mm monster rotor kit

Maybe a Jack Shaft kit eventually


Wish me luck, I should start wrenching this weekend or early next week


Finally riding

 

[wheelbender6]

Welcome to the forum. I can feel your enthusiasm, but don't rush thru your build. Get one thing right before moving onto the next.
The Dawes looks like a great bike but that fat down tube will probably require an over-sized front engine mount.
The other thing I suggest is that you get your engine installed and running smooth in stock trim before adding all those other goodies. We (non-experts) have to build these things in a methodical fashion or troubleshooting problems becomes very very complicated. Enjoy your build. As you said, the build is part of the journey.

 

[KCvale]

I bought a 19“ mtb with front suspension from bikes direct, I plan on building a decent mtb that happens to have an 80cc motor.

http://www.bikesdirect.com/products/dawes/hay1000xi.htm

Disc brakes, lock out forks and it was cheap.

Got it, put it together, rode it. Now I'm waiting on my motor.

Quick tip, there is no such thing as 80cc, they are all 66cc.

I'm afraid you are going to be in for a horrible surprise, I don't a think a 2-stroke is gonna fit in that 19" frame even with a slant head rotated to face forward.

The engine will have to sit so high the top will hit the top bar.

Assuming it will fit you will find you have to jackshaft it if you have a rear disc brake, no place to mount a direct drive sprocket unless you sacrifice the rear disc which would be silly so figure $200 more the JS kit but you can return some of the silly stuff you ordered below

Parts ordered

Dual pull lever
Sram thumb shifter sans brake levers

That makes no sense.
Let me help steer you in the right direction assuming your engine will even fit.

Regardless of it being a direct drive or a jackshafted shifter there is only room for 2 pull levers and 2 twist controls on the handlebars if you want it to be safe to operate not just for yourself, but anyone else you let ride it.

You ordered the sickbikeparts self adjusting dual pull, good, you'll need it as the clutch lever goes on the left.

This is how I do all my 2-stroke handlebars if it has pedal gears.

All the bikes brake and shift controls are removed including the whole front derailleur system and it's controller.

Just pay attention to the main control layout and not the extra stuff I do with grips and such.

Dual pull brake lever and throttle on the right.
ROTARY rear gear shifter and clutch on the left.

Just my advice, take it or leave it, but I've built a lot of bikes and this handlebar layout has proven to be the best you can get in many ways.

 

[Rudz]

Thanks guys. Still waiting for the motor , been praying it fits.


I got the tophat mod from Kings because it mounts the disc rotor and drive gear to the rear disc hub.

Kc thanks a lot I love your builds. I'll keep you updated. If hoping I have room for the thumb shifters, if not I'll use the twist

One thing I'm worried about is whether or not the chain will clear 2.5" tires

 

[Rudz]

Motor finally showed up. It's going to be a tight fit, unfortunately the kit didn't come with a slant head.

I was under the impression the kit came with the slant head, I ordered one, without it there's probably not room for the spark plug cable. Lmfao

I also ordered a offset extended manifold, I wanted one anyway. Now I need one.

Also made my first screw up, forcing the bottom head gasket on I ripped it. Maybe I should have oiled it first?

My kit came with the top disassembled, so I'll be putting that together. While I'm waiting for my gasket, head and manifold to arrive.

My batwing bars look great, still waiting on the tophat adapter.

The stock throttle is cheap crap. The sbp one is going to be necessary. I did receive a longer clutch handle. No instructions. I did find some online though

The back paint on this thing is horrible I'm going to have to sand down a lot of things

 

[KCvale]

Bummer man.
I know what it's like to see it in your head but have it turn out to be mechanically impossible to do.

IF you can get the engine to fit I highly recommend you jackshaft.
Maybe there some direct sprocket that will mount with your disc rotor for a direct drive but why?

I have offered all the help I can and wish you the best of success on your build, I'll keep tabs on it and look forward to seeing how you deal with all the obstetricals in front of you.

 

[Rudz]

Before the havoc





Oh the obstacles. Lmfao, I started off with my handlebar, in my haste of parts ordering I forgotten to buy a 31.8 stem for my batwing bar. Shucks.

I did eventually get the clutch and grip on the left, thumb shifter, dial broke lever, kill switch and throttle on the right.

It wasn't easy. Luckily the bars are wide and have a nice straight area to work with.

First problem was the brake was tight, I probably should have sanded the inside of the brake lever mount but I was being lazy. Instead I oiled the bar with some painting until oil and coaxed/muscled it on.

Got the shifter where I wanted, but when I finally got the throttle figured out, it was not going to work. So I grinded down part of the shifter lever for clearance and it worked fantastic.

Got everything where I wanted and it looks great. I'll post pictures when I get my stem.

I decided to tackle the rear wheel next. I have my disc brake adapter and drive gear in hand, just have to remove the disc caliper bolts. 5 down, one more, it strips!

Many curses were said. I slotted it and still it wouldn't come out. I'm going to have to try and use an easy out kit to remove it, then replace all those bolts with stainless.

I also installed some better than stock pedals I had laying around, removed the front derailleur and cable.

Fixed the fender on my road bike, have one working bicycle, I'm happy.

Made decent progress.

 

[Rudz]

I drilled and grinded the bolt that was giving me fits yesterday, got the rotor off and used vise grips to turn the bolt out.

I was going to try and enlarge the hole in the stocks sprocket to use the tophat mod, unfortunately using only a dremmel I think it would take far too long.

Looks like I'm buying a new sprocket from Kings with a larger center hole.

At least I got that bolt off. That makes me happy

 

[Rudz]

Getting started





Batwing bars



Kill switch underneath




Top of bar with grinded down lever

 

[Davezilla]

Looks like you're getting past the obstacles pretty well, but you'll still have a few more to get past, getting that engine to fit into a 19" frame won't be easy, I know because I did mine in a 20" frame and there's not much room once everything is in place, especially at the seat post area... there's very little room for the carb and air filter so I have to remove the filter to get the carb on and off, then re install the filter after the carb is in place, not to mention custom filters won't work unless you get an offset air inlet duct. You can get an offset intake manifold that'll eliminate that problem by placing the carb next to the seat post instead of in front of it, and the longer intake will also give you better low end torque.

I had to modify the rear mount block by cutting off all but the cradle part of the block, so basically about 3/4". That let the engine go into place then up front I have an oversized front tube, and it's oval instead of round so I originally used some really long studs in the front mount, but after battling lots of engine vibration I decided to cut slots into my lower frame tube and welding a steel bar theu it to mount the engine directly to the tabs sticking out of the frame.
I'm using a Fred head because the slant plug head left me no room for the spark plug unless I took the head off and reversed it, but the Fred head is nice for performance and keeping the top end nice and cool, there's maybe about 1/4" clearance between the head and the top tube.
Once you get the engine mounted where it sits securely in the frame, the rest should be pretty easy.

The tank may give you some trouble but if you use some rubber pads made either from an old grip cut up or a section of inner tube between the tank and frame and fit it as far forward as possible you should be ok there, double sided tape works wonders here.

Main thing is just take your time and don't try to rush anything as you get things to fit, make sure the engine sits very solid and securely, and be sure the chain lines up really well and it should work just fine for you.

 

[Rudz]

I mocked up the engine and it should fit with a slant head. I ordered an extended offset manifold for the carburetor

I was grinding the stock sprocket to make it work with the top hat mod but it's taking forever and my neighbors are probably sick of me sitting outside with the grinder by now. And it's still not done.

I'm probably going to bite the bullet and buy the right sprocket from Kings or Jake

I have epoxy for the tank mounting, I'm going to make a bridge for the cables to run through and not interfere with the tank. I think I'll need wider mounting brackets first though

 

[Rudz]

I just realized the huge one gallon tank I want is 14" long. That's almost the entire length of my top tube! I'm curious how that would look. I actually think it might be awesome

Trying to get an old machinist buddy to finish milling my stock sprocket for the disc clearance. I'm trying hard not to buy a new one. But at the same time I done feel like spending hours grinding still. Plus his work would looks nicer

 

[Davezilla]

What looks really good on MTB frames if you want a bigger tank are those Honda clone pitbike tanks, they're plastic and have a cool shape to them and cost about $30... Here's one I got on my ebay watch list... http://www.ebay.com/itm/390669428393?ssPageName=STRK:MESINDXX:IT&_trksid=p3984.m1436.l2649 these look kinda plain as is, but you can get the cover panels in just about any color to finish the look and then they look cool... You will need to make up some brackets tho to get one of these to fit right.

The stock tank does look good on a MTB tho and will give you about a 60 mile range.

I'll eventually be switching to this type of tank but I'm still in the process of doing several improvements to mine so I won't really worry about getting the tank until I'm closer to ready to take it back apart and paint it.

Trying to dremel a sprocket to enlarge a center hole can be quite time consuming, I'd be looking to have somebody at a machine shop do that job for me too if I didn't have the machinery to do it. Luckily mine fit the first try. If you have a set of carbide rotary files for the dremel tho it'll speed up that job considerably.

 

[Rudz]

Found my carbide bit! Screw you sprocket! I win. Whew that little bit saved me a lot of headache that's for sure. I was going nowhere with the grinding bit.

I'm going to order longer m5 stainless steel bolts to mount everything to the hub. Haven't decided if I'm going to cut down the stock 3/16 bolts of get new ones from Home Depot. I like the stock bolts because of the low profile.

Anyways, one of my hurdles is over.

I looked at the tank today's, the top tube is so thick that the bolts barely reach the bottom of the tube. If I have some longer straps I could make it work though. The clearance for some bolts though, that's going to be tight

 

[Davezilla]

Glad to hear you had a carbide bit to use, they're a real timesaver... IF you need to get more of these, don't spend $10 each for them at Home Depot or other places... I got this set on ebay for arouns $25 and these fit the dremel http://www.ebay.com/itm/171354864070?_trksid=p2059210.m2749.l2649&ssPageName=STRK:MEBIDX:IT
They don't get used very much here because I usually use a bigger die grinder, but these are great for smaller jobs or when I don't want to run my compressor, no worries about dulling these...

For the tank, you can probably make some longer (and more durable) straps if your top tube is too big around, just be careful not to overtighten the nuts because the studs are spot welded on pretty weak, Most of us just use some rubber from a cut up grip or inner tube along with some double sided tape to keep the tank from moving around and so we can use less torque on the tank hardware which works really good.

 

[Rudz]

I just ordered a carbide set and the dremel flex shaft extension so I can do the porting and polishing

Also bought a 4L tank, some mounting hardware for my wheel.

My slant head, offset manifold and stem showed u today. No time to play with in. I work tonight.

Going to order an air filter, brass fuel filter and wide tank brackets from Lynne if she has them in stock. Waiting for an email reply.


I should have everything I need to get the bike running next week. Mainly waiting on the wheel hardware. Stainless steel bolts that go through the disc, top hat and sprocket into the hub.

I have a few ideas of how to mount the tank

 

[Rudz]

Never heard from Lynne so I ordered a KN type filter, Briggs glass bowl fuel filter and brass fitting, blue fuel line and a brass petcock. Alsop bought a 410 chain, in case the 415 is too thick.

Wide tank mounts and sprocket tool en route as well.

My new tank and gasket showed up. I'll probably port the jug this weekend. I wanted to clean up the posts before I mount it all up. I don't want to have to rip it apart again.

The last things on my to buy list are torque 2 pipe from Arrow, CDI, spring saddle and new tires.

I haven't decided on the CDI or tires yet. If I can use Hookworms I will, if not Marathon Plus or Supreme

 

[Rudz]

I assembled my motor today. Made sure I got the gasket on the right way so I didn't rip it this time.

I watched enough videos to know that the piston rings have to sit in the groove to be able to slide into the jug.

I made sure the bearing, rod and clips went in right. Arrow side of piston is facing the exhuast. Mounted the manifold and carburetor.

I need to trim down the front post mounts, as I'm using the wide downtube adapter anyways. The posts are creating too much space between the engine and my downtube so they need to be trimmed.

Think I'll trim the rear mounts as well. They're much-needed to long for my frame.

With the offset manifold and slanted head the motorized fits in my frame. Barely.

I also worked on the rear wheel, got the trimmed the 9 bolts and mounted the sprocket /tophat to the hub. I had to make a shim for the axle because the brave was rubbing the frame. I still need another for the opposite side.

Also realize that I need to add a spacer between the sprocket and disc rotor so my caliber will fit. Hopefully I can use the same bolts, otherwise I have to find more, trim those downhill to fit as well.

Mounted my bars with the new stem, slammed the seat post and it feels good.

I work tonight, but hopefully I car mount the motor this weekend and hook up the rear derailleur and front brake at least. I'll try to get the rear brake situated but now promises.

 

[Rudz]

Finally mounted the motor. I still need to add rubber, so it's not final. I mocked up the gas tank and bent the mount, I still need to make a bridge for the wires that run along the top tube

Fought with the rear wheel quite a bit. I added spacers so the caliper could fit between the rotor and sprocket. Didn't work, I had already cut the bolts, so I could only add so many spacers

I figured I could grind the caliper down, after grinding it within a mm of its life I tested it, and it still won't fit.

So, I can add more spacers and get longer bolts, but I'm worried about the chain line too close to the tire. I can figure out how to put caliper brakes on a frame with no studs.

Of I can run the front brake until I buy a shift kit. Lmfao.


I'm going to work on everything else because that rear wheel is irritating me so much.

 

[Rudz]

I finished eating, rinsed off, relaxed and went back to work.


I had already started mounting the tensioner, I had to use the mounting bracket in the kit because the one that came with my spring tensioner wasn't going to fit my chainstay


The tank is just slapped on for the picture to show how massive it really is.



Cdi mounted and thankfully the exhuast clears the pedals. Heck I wasn't sure if it way going to clear my massive down tube, the wide mounding brackets barely fit.

I'm done for the night. Finish the tensioner tomorrow, run the cables, mount the tank.

It's getting there.