New Bofeng carb

[gearhead437]

Your referring to viton o-rings but they can be any color I believe.

Dear Fello Motorheads-Appreciate the reply. I did receive the correct size O-ring with my BoFeng carburator, but have no clue what it's made out of. Hoping that it's Nitrile rubber. Will IM EBay seller. Does anyone have any experience with this O-ring? Finally got brave and opened my Storehouse brand HF 180 piece Viton O-ring assortment . Discovered that A016 (5 pieces) and A113 (10 pieces), are a VERY close fit. One is a hair oversized, but seats in the carb, just as the other is a hair undersized but safely seats inside the carb. Forgot to add, but Honda used to use Hondabond instead of gaskets between their 4 cyclinder engine blocks and the tranny- that's how I found out about it. Very sticky, resilient and leakproof. Used it on my Grubbee 49cc when I had a leaking intake. NOT cheap and you must order it via mail. Around $15-18.00, but definitely worth it-My dollars worth-Gearhead437
UPDATE:-Included are pictures of the stock BoFeng O-ring, the slightly undersized HF A016 Viton O-ring and the slightly oversized (but thinner) HF A113 Viton O-ring. I was told by an HVAC buddy to use a little silicone lube on the Viton ring to facilitate seating. Was also told that the thicker Viton O-ring will do a better job of sealing. Hope to hear back from the vendor on the composition of their O-ring.-Gearhead437

 

[gearhead437]

 

[ImpulseRocket]

Honda used to use Hondabond instead of gaskets between their 4 cyclinder engine blocks and the tranny- that's how I found out about it. Very sticky, resilient and leakproof.

They still do use Hondabond for case sealing. There are even a few different types of Hondabond depending on what and where the sealing needs to take place. I had to buy 3 different types when I split the case on my VFR1200. The only gaskets on that entire engine are the head gasket. Everything else is either a type of O ring seal or just Hondabond.


If you are looking for a good O ring for said carbs 19mm OD 1.5mm thickness : https://www.walmart.com/ip/2PC-O-Ri...645414?wmlspartner=wlpa&selectedSellerId=1772

I like to use 15mm ID x 19mm OD x 2mm O-rings. I ordered a few of these specific ones and they work well. $3.50 for 5 and free shipping. Hard to beat. https://www.ebay.com/itm/2939073609...rt7TyM6DZfDE2yOJx0c-NvAyVmtpt7vLhssUnnRiJA0ME

 

[gearhead437]

They still do use Hondabond for case sealing. There are even a few different types of Hondabond depending on what and where the sealing needs to take place. I had to buy 3 different types when I split the case on my VFR1200. The only gaskets on that entire engine are the head gasket. Everything else is either a type of O ring seal or just Hondabond.


If you are looking for a good O ring for said carbs 19mm OD 1.5mm thickness : https://www.walmart.com/ip/2PC-O-Ri...645414?wmlspartner=wlpa&selectedSellerId=1772

I like to use 15mm ID x 19mm OD x 2mm O-rings. I ordered a few of these specific ones and they work well. $3.50 for 5 and free shipping. Hard to beat. https://www.ebay.com/itm/2939073609...rt7TyM6DZfDE2yOJx0c-NvAyVmtpt7vLhssUnnRiJA0ME

Appreciate the solid and detailed feedback, ImpulseRocket-PM sent-Gearhead437

 

[gearhead437]

Appreciate the solid and detailed feedback, ImpulseRocket-PM sent-Gearhead437

Dear Fellow Motorheads,
Thanx to this forum, I was able to discover the BoFeng carb and successfully install one, after applying a little pure silicone oil to the O-ring. I had to carefully press on the carb assembly while tightening the carb clamp to ensure that the O-ring seated and wasn't sucked into the engine (thanx Jayraye). For whatever reason, the small washer that sits on top of the carb needle and e-clip kept falling out and was a bugger to keep in place while installing the throttle cable. I carefully measured the contact depth of the O-ring and marked this on the intake tube, using a marker. I also had to file off a little casting flash on the intake tube at this point, as the carb petals would have contacted it otherwise. Interference fit between the carb and intake tube was great! I replaced the fuel line and some of the clamps to ensure no leaks and set the carb to full choke. At full choke on my carb, there was so little air that I could not rev the carb at all, and so had to back off on this to ensure a succesful start. Amazingly, that little BoFeng took very little time to fill up with fuel and the idle was VERY close before adjustment. The idle is MUCH improved over the carb that came with my kit. Using a new intake tube gasket and Hondabond is highly recommended, as this prevents the cheap paper gasket from becoming soaked with fuel and possibly leaking air. For $12.00, this BoFeng is a HUGE improvement over the carb that came with my kit and I highly recommend buying one if you are diasppointed with your present stock carb. YMMV and this is just my .02-Gearhead437

 

[gearhead437]

UPDATE-Does anyone recommend using blue Loctite to prevent the carb clamp bolt from loosening up from its square nut? I am very worried about breaking one of the 4 cast petals that are part of the carb body, as I carefully tightened the clamp bolt using a Metric 10mm socket head. As mentioned before on the forum, even the carb clamp and it's fastener are superior in design to the NT carb clamp and fastener. Thanx again for any detailed and constructive feedback-Gearhead437.

 

[DAMIEN1307]

Does anyone recommend using blue Loctite to prevent the carb clamp bolt from loosening up from its square nut?

I've never used locktite of any sort on the carburetor fasteners whatsoever and have never had a loosening problem with them.

 

[ImpulseRocket]

If you experience it loosening, sure. The tension of the clamp already acts as a means of retention for the hardware.

 

[GW's Motorized]

Just buy some better hardware. I put a hex cap bolt and nylock nut on my bt80

 

[gearhead437]

Dear Damien, Impulse Rocket and GW's Motorized-Thanx for the solid feedback. The provided carb. clamp machine bolt works great with a 10mm socket-Besides its loosening, I am also worried about overtightening and breaking a cast petal off of the carb. The NT carb clamp had difficulty staying tight and I don't want the carb loosening up and the engine inhaling the O-ring! Of course, the BoFeng carb clamp is superior in every way to the NT clamp. As you can see from the picture, the BoFeng carb even looks better than the NT, as my engine has black stickers on it and the Hypercruiser bike is black. Hard to beat for a $12.00 carb!-Gearhead437