The Model X is about to give Tesla a 'reality check'

Tesla may be in for a reality check.

In a note on Friday, Barclays' Brian Johnson detailed why the electric-car company's brand new Model X SUV may fail to meet the company's expectations for production and put pressure on margins.

As a result, Johnson and his team lowered their price target 5% to $190 from $180, and cut their rating to "Underweight" from "Equal-Weight."

Johnson wrote that estimates for Tesla's margins are likely overestimated, and the company is about to get a "reality check":

Model X will provide yet another reality check on margins. We see several factors pushing margins below current consensus expectations - engineering challenges will lead to manufacturing challenges (i.e. "Elon's headache"), the production ramp will be slow, and Tesla will be challenged in concurrent S/X production

The Model X launch had been delayed for about two years; CEO Elon Musk later said it was the most difficult car ever built.

And according to Barclays, there are even more engineering challenges ahead that will slow down manufacturing even though the company is more efficient today than it was when the Model S launched in 2012.

Barclays also projected that Tesla would likely miss its production guidance for 2015 of delivering 50,000 to 55,000 cars.

The firm also already doubts that Tesla will release the forthcoming Model 3 on time in 2017.

They also lowered their expectations for Tesla Energy, because there is fierce competition in the power storage space, and they're not clear whether Tesla's Powerwall battery is superior.

On Tuesday, Morgan Stanley's Adam Jonas cut his super bullish price target on the stock and wrote in a note that the Model X was more expensive than they had expected.

Tesla shares fell as much as 3% in early trading to around $219.26.